Allow moving cursors between connected displays.

* Use ComputeBoundary to detect edges instead of using DisplayPlacement.
* This also fixes a bug where wrong key was used when saving preference.

BUG=597274
TEST=covered by unit tests.

Review URL: https://codereview.chromium.org/1823913002

Cr-Commit-Position: refs/heads/master@{#383153}

11 files changed, 450 insertions, 276 deletions

diff --git a/ash/display/display_layout_store.cc b/ash/display/display_layout_store.cc
index 1deb3a4..faec7ab 100644
--- a/ash/display/display_layout_store.cc
+++ b/ash/display/display_layout_store.cc
@@ -50,6 +50,10 @@ void DisplayLayoutStore::SetDefaultDisplayPlacement(
 void DisplayLayoutStore::RegisterLayoutForDisplayIdList(
     const DisplayIdList& list,
     scoped_ptr<DisplayLayout> layout) {
+  // A dev/beta channel may have a bad layout data saved in local state.
+  // TODO(oshima): Consider removing this a coulpe of milestones later.
+  if (list.size() == 2 && layout->placement_list.size() > 1)
+    return;
 
   // Do not overwrite the valid data with old invalid date.
   if (layouts_.count(list) && !CompareDisplayIds(list[0], list[1]))
@@ -67,7 +71,9 @@ void DisplayLayoutStore::RegisterLayoutForDisplayIdList(
       layout->placement_list[0].parent_display_id = list[0];
     }
   }
-  DCHECK(DisplayLayout::Validate(list, *layout.get())) << layout->ToString();
+  DCHECK(DisplayLayout::Validate(list, *layout.get()))
+      << "ids=" << DisplayIdListToString(list)
+      << ", layout=" << layout->ToString();
   layouts_[list] = std::move(layout);
 }
 
diff --git a/ash/display/display_manager_unittest.cc b/ash/display/display_manager_unittest.cc
index 9be39e9..7e98711 100644
--- a/ash/display/display_manager_unittest.cc
+++ b/ash/display/display_manager_unittest.cc
@@ -1999,6 +1999,19 @@ TEST_F(DisplayManagerTest, DockMode) {
   EXPECT_FALSE(SetDisplayUIScale(gfx::Display::kInvalidDisplayID, 1.0f));
 }
 
+// Make sure that bad layout information is ignored and does not crash.
+TEST_F(DisplayManagerTest, DontRegisterBadConfig) {
+  if (!SupportsMultipleDisplays())
+    return;
+  DisplayIdList list = ash::test::CreateDisplayIdList2(1, 2);
+  DisplayLayoutBuilder builder(1);
+  builder.AddDisplayPlacement(2, 1, ash::DisplayPlacement::LEFT, 0);
+  builder.AddDisplayPlacement(3, 1, ash::DisplayPlacement::BOTTOM, 0);
+
+  display_manager()->layout_store()->RegisterLayoutForDisplayIdList(
+      list, builder.Build());
+}
+
 class ScreenShutdownTest : public test::AshTestBase {
  public:
   ScreenShutdownTest() {
@@ -2029,7 +2042,6 @@ TEST_F(ScreenShutdownTest, ScreenAfterShutdown) {
   UpdateDisplay("500x300,800x400");
 }
 
-
 #if defined(OS_CHROMEOS)
 namespace {
 
diff --git a/ash/display/display_util.cc b/ash/display/display_util.cc
index 7c1b7c9..02fa6c9 100644
--- a/ash/display/display_util.cc
+++ b/ash/display/display_util.cc
@@ -222,7 +222,7 @@ bool HasDisplayModeForUIScale(const DisplayInfo& info, float ui_scale) {
   return std::find_if(modes.begin(), modes.end(), comparator) != modes.end();
 }
 
-void ComputeBoundary(const gfx::Display& a_display,
+bool ComputeBoundary(const gfx::Display& a_display,
                      const gfx::Display& b_display,
                      gfx::Rect* a_edge_in_screen,
                      gfx::Rect* b_edge_in_screen) {
@@ -240,18 +240,20 @@ void ComputeBoundary(const gfx::Display& a_display,
     // top bottom
     if (a_bounds.bottom() == b_bounds.y()) {
       position = DisplayPlacement::BOTTOM;
-    } else {
-      DCHECK_EQ(a_bounds.y(), b_bounds.bottom());
+    } else if (a_bounds.y() == b_bounds.bottom()) {
       position = DisplayPlacement::TOP;
+    } else {
+      return false;
     }
   } else {
-    DCHECK((rr - rx) == 0);
     // left right
     if (a_bounds.right() == b_bounds.x()) {
       position = DisplayPlacement::RIGHT;
-    } else {
-      DCHECK_EQ(a_bounds.x(), b_bounds.right());
+    } else if (a_bounds.x() == b_bounds.right()) {
       position = DisplayPlacement::LEFT;
+    } else {
+      DCHECK_NE(rr, rx);
+      return false;
     }
   }
 
@@ -278,11 +280,12 @@ void ComputeBoundary(const gfx::Display& a_display,
         b_edge_in_screen->SetRect(b_bounds.right() - 1, top, 1, bottom - top);
       } else {
         a_edge_in_screen->SetRect(a_bounds.right() - 1, top, 1, bottom - top);
-        b_edge_in_screen->SetRect(b_bounds.y(), top, 1, bottom - top);
+        b_edge_in_screen->SetRect(b_bounds.x(), top, 1, bottom - top);
       }
       break;
     }
   }
+  return true;
 }
 
 gfx::Rect GetNativeEdgeBounds(AshWindowTreeHost* ash_host,
@@ -383,7 +386,13 @@ void SortDisplayIdList(DisplayIdList* ids) {
 }
 
 std::string DisplayIdListToString(const ash::DisplayIdList& list) {
-  return base::Int64ToString(list[0]) + "," + base::Int64ToString(list[1]);
+  std::stringstream s;
+  const char* sep = "";
+  for (int64_t id : list) {
+    s << sep << id;
+    sep = ",";
+  }
+  return s.str();
 }
 
 bool CompareDisplayIds(int64_t id1, int64_t id2) {
diff --git a/ash/display/display_util.h b/ash/display/display_util.h
index f48ad34..3267d70 100644
--- a/ash/display/display_util.h
+++ b/ash/display/display_util.h
@@ -63,7 +63,8 @@ ASH_EXPORT bool SetDisplayUIScale(int64_t display_id, float scale);
 bool HasDisplayModeForUIScale(const DisplayInfo& info, float ui_scale);
 
 // Computes the bounds that defines the bounds between two displays.
-void ComputeBoundary(const gfx::Display& primary_display,
+// Returns false if two displays does not intersect.
+bool ComputeBoundary(const gfx::Display& primary_display,
                      const gfx::Display& secondary_display,
                      gfx::Rect* primary_edge_in_screen,
                      gfx::Rect* secondary_edge_in_screen);
diff --git a/ash/display/display_util_unittest.cc b/ash/display/display_util_unittest.cc
index 14e3b03..10866ba 100644
--- a/ash/display/display_util_unittest.cc
+++ b/ash/display/display_util_unittest.cc
@@ -98,12 +98,26 @@ TEST_F(DisplayUtilTest, GenerateDisplayIdList) {
     list = GenerateDisplayIdList(std::begin(ids), std::end(ids));
     EXPECT_EQ(1, list[0]);
     EXPECT_EQ(10, list[1]);
+
+    int64_t three_ids[] = {10, 5, 1};
+    list = GenerateDisplayIdList(std::begin(three_ids), std::end(three_ids));
+    ASSERT_EQ(3u, list.size());
+    EXPECT_EQ(1, list[0]);
+    EXPECT_EQ(5, list[1]);
+    EXPECT_EQ(10, list[2]);
   }
   {
     int64_t ids[] = {10, 100};
     list = GenerateDisplayIdList(std::begin(ids), std::end(ids));
     EXPECT_EQ(10, list[0]);
     EXPECT_EQ(100, list[1]);
+
+    int64_t three_ids[] = {10, 100, 1000};
+    list = GenerateDisplayIdList(std::begin(three_ids), std::end(three_ids));
+    ASSERT_EQ(3u, list.size());
+    EXPECT_EQ(10, list[0]);
+    EXPECT_EQ(100, list[1]);
+    EXPECT_EQ(1000, list[2]);
   }
   {
     test::ScopedSetInternalDisplayId set_internal(100);
@@ -116,6 +130,13 @@ TEST_F(DisplayUtilTest, GenerateDisplayIdList) {
     list = GenerateDisplayIdList(std::begin(ids), std::end(ids));
     EXPECT_EQ(100, list[0]);
     EXPECT_EQ(10, list[1]);
+
+    int64_t three_ids[] = {10, 100, 1000};
+    list = GenerateDisplayIdList(std::begin(three_ids), std::end(three_ids));
+    ASSERT_EQ(3u, list.size());
+    EXPECT_EQ(100, list[0]);
+    EXPECT_EQ(10, list[1]);
+    EXPECT_EQ(1000, list[2]);
   }
   {
     test::ScopedSetInternalDisplayId set_internal(10);
@@ -128,6 +149,27 @@ TEST_F(DisplayUtilTest, GenerateDisplayIdList) {
     list = GenerateDisplayIdList(std::begin(ids), std::end(ids));
     EXPECT_EQ(10, list[0]);
     EXPECT_EQ(100, list[1]);
+
+    int64_t three_ids[] = {10, 100, 1000};
+    list = GenerateDisplayIdList(std::begin(three_ids), std::end(three_ids));
+    ASSERT_EQ(3u, list.size());
+    EXPECT_EQ(10, list[0]);
+    EXPECT_EQ(100, list[1]);
+    EXPECT_EQ(1000, list[2]);
+  }
+}
+
+TEST_F(DisplayUtilTest, DisplayIdListToString) {
+  {
+    int64_t ids[] = {10, 1, 16};
+    DisplayIdList list = GenerateDisplayIdList(std::begin(ids), std::end(ids));
+    EXPECT_EQ("1,10,16", DisplayIdListToString(list));
+  }
+  {
+    test::ScopedSetInternalDisplayId set_internal(16);
+    int64_t ids[] = {10, 1, 16};
+    DisplayIdList list = GenerateDisplayIdList(std::begin(ids), std::end(ids));
+    EXPECT_EQ("16,1,10", DisplayIdListToString(list));
   }
 }
 
diff --git a/ash/display/extended_mouse_warp_controller.cc b/ash/display/extended_mouse_warp_controller.cc
index 879b04b..26a199d 100644
--- a/ash/display/extended_mouse_warp_controller.cc
+++ b/ash/display/extended_mouse_warp_controller.cc
@@ -31,8 +31,6 @@ const int kMaximumSnapHeight = 16;
 // this, entire edge will be used as a draggable space.
 const int kMinimumIndicatorHeight = 200;
 
-const int kIndicatorThickness = 1;
-
 // Helper method that maps a gfx::Display to an aura::Window.
 aura::Window* GetRootWindowForDisplayId(int64_t display_id) {
   return Shell::GetInstance()
@@ -40,9 +38,25 @@ aura::Window* GetRootWindowForDisplayId(int64_t display_id) {
       ->GetRootWindowForDisplayId(display_id);
 }
 
-// Helper method that maps an aura::Window to a gfx::Display.
-gfx::Display GetDisplayFromWindow(aura::Window* window) {
-  return gfx::Screen::GetScreen()->GetDisplayNearestWindow(window);
+// Helper method that maps an aura::Window to display id;
+int64_t GetDisplayIdFromWindow(aura::Window* window) {
+  return gfx::Screen::GetScreen()->GetDisplayNearestWindow(window).id();
+}
+
+// Adjust the edge so that it has |barrier_size| gap at the top to
+// trigger snap window action.
+void AdjustSourceEdgeBounds(const gfx::Rect& display_bounds,
+                            int barrier_size,
+                            gfx::Rect* edge) {
+  DCHECK_GT(edge->height(), edge->width());
+  int target_y = display_bounds.y() + barrier_size;
+  if (target_y < edge->y())
+    return;
+
+  int available_height = edge->height() - kMinimumIndicatorHeight;
+  if (available_height <= 0)
+    return;
+  edge->Inset(0, std::min(available_height, target_y - edge->y()), 0, 0);
 }
 
 }  // namespace
@@ -72,29 +86,32 @@ ExtendedMouseWarpController::WarpRegion::WarpRegion(
 
 ExtendedMouseWarpController::WarpRegion::~WarpRegion() {}
 
+const gfx::Rect&
+ExtendedMouseWarpController::WarpRegion::GetIndicatorBoundsForTest(
+    int64_t id) const {
+  if (a_display_id_ == id)
+    return a_indicator_bounds_;
+  CHECK_EQ(b_display_id_, id);
+  return b_indicator_bounds_;
+}
+
 ExtendedMouseWarpController::ExtendedMouseWarpController(
     aura::Window* drag_source)
     : drag_source_root_(drag_source),
       allow_non_native_event_(false) {
   ash::DisplayManager* display_manager =
       Shell::GetInstance()->display_manager();
-
-  // TODO(oshima): Use ComputeBondary instead and try all combinations.
-  for (const auto& placement :
-       display_manager->GetCurrentDisplayLayout().placement_list) {
-    DisplayPlacement::Position position = placement.position;
-    const gfx::Display& a =
-        display_manager->GetDisplayForId(placement.parent_display_id);
-    const gfx::Display& b =
-        display_manager->GetDisplayForId(placement.display_id);
-
-    if (position == DisplayPlacement::TOP ||
-        position == DisplayPlacement::BOTTOM) {
-      AddWarpRegion(CreateHorizontalEdgeBounds(a, b, position),
-                    drag_source != nullptr);
-    } else {
-      AddWarpRegion(CreateVerticalEdgeBounds(a, b, position),
-                    drag_source != nullptr);
+  int64_t drag_source_id = drag_source ? GetDisplayIdFromWindow(drag_source)
+                                       : gfx::Display::kInvalidDisplayID;
+  DisplayList display_list = display_manager->active_display_list();
+  while (display_list.size() > 0) {
+    gfx::Display display = display_list.back();
+    display_list.pop_back();
+    for (const gfx::Display& peer : display_list) {
+      scoped_ptr<WarpRegion> region =
+          CreateWarpRegion(display, peer, drag_source_id);
+      if (region)
+        AddWarpRegion(std::move(region), drag_source != nullptr);
     }
   }
 }
@@ -179,92 +196,27 @@ bool ExtendedMouseWarpController::WarpMouseCursorInNativeCoords(
 }
 
 scoped_ptr<ExtendedMouseWarpController::WarpRegion>
-ExtendedMouseWarpController::CreateHorizontalEdgeBounds(
-    const gfx::Display& a,
-    const gfx::Display& b,
-    DisplayPlacement::Position position) {
-  bool from_a = a.id() == GetDisplayFromWindow(drag_source_root_).id();
-
-  const gfx::Rect& a_bounds = a.bounds();
-  const gfx::Rect& b_bounds = b.bounds();
-
-  gfx::Rect a_indicator_bounds;
-  a_indicator_bounds.set_x(std::max(a_bounds.x(), b_bounds.x()));
-  a_indicator_bounds.set_width(std::min(a_bounds.right(), b_bounds.right()) -
-                               a_indicator_bounds.x());
-  a_indicator_bounds.set_height(kIndicatorThickness);
-  a_indicator_bounds.set_y(
-      position == DisplayPlacement::TOP
-          ? a_bounds.y() - (from_a ? 0 : kIndicatorThickness)
-          : a_bounds.bottom() - (from_a ? kIndicatorThickness : 0));
-
-  gfx::Rect b_indicator_bounds;
-  b_indicator_bounds = a_indicator_bounds;
-  b_indicator_bounds.set_height(kIndicatorThickness);
-  b_indicator_bounds.set_y(
-      position == DisplayPlacement::TOP
-          ? a_bounds.y() - (from_a ? kIndicatorThickness : 0)
-          : a_bounds.bottom() - (from_a ? 0 : kIndicatorThickness));
-
-  return make_scoped_ptr(
-      new WarpRegion(a.id(), b.id(), a_indicator_bounds, b_indicator_bounds));
-}
-
-scoped_ptr<ExtendedMouseWarpController::WarpRegion>
-ExtendedMouseWarpController::CreateVerticalEdgeBounds(
-    const gfx::Display& a,
-    const gfx::Display& b,
-    DisplayPlacement::Position position) {
-  int snap_height = drag_source_root_ ? kMaximumSnapHeight : 0;
-  bool in_a = a.id() == GetDisplayFromWindow(drag_source_root_).id();
-
-  const gfx::Rect& a_bounds = a.bounds();
-  const gfx::Rect& b_bounds = b.bounds();
-
-  int upper_shared_y = std::max(a_bounds.y(), b_bounds.y());
-  int lower_shared_y = std::min(a_bounds.bottom(), b_bounds.bottom());
-  int shared_height = lower_shared_y - upper_shared_y;
-
-  gfx::Rect a_indicator_bounds;
-  gfx::Rect b_indicator_bounds;
-
-  int dst_x = position == DisplayPlacement::LEFT
-                  ? a_bounds.x() - (in_a ? kIndicatorThickness : 0)
-                  : a_bounds.right() - (in_a ? 0 : kIndicatorThickness);
-  b_indicator_bounds.SetRect(dst_x, upper_shared_y, kIndicatorThickness,
-                             shared_height);
-
-  // The indicator on the source display.
-  a_indicator_bounds.set_width(kIndicatorThickness);
-  a_indicator_bounds.set_x(position == DisplayPlacement::LEFT
-                               ? a_bounds.x() - (in_a ? 0 : kIndicatorThickness)
-                               : a_bounds.right() -
-                                     (in_a ? kIndicatorThickness : 0));
-
-  const gfx::Rect& source_bounds = in_a ? a_bounds : b_bounds;
-  int upper_indicator_y = source_bounds.y() + snap_height;
-  int lower_indicator_y = std::min(source_bounds.bottom(), lower_shared_y);
-
-  // This gives a hight that can be used without sacrifying the snap space.
-  int available_space =
-      lower_indicator_y - std::max(upper_shared_y, upper_indicator_y);
-
-  if (shared_height < kMinimumIndicatorHeight) {
-    // If the shared height is smaller than minimum height, use the
-    // entire height.
-    upper_indicator_y = upper_shared_y;
-  } else if (available_space < kMinimumIndicatorHeight) {
-    // Snap to the bottom.
-    upper_indicator_y =
-        std::max(upper_shared_y, lower_indicator_y + kMinimumIndicatorHeight);
-  } else {
-    upper_indicator_y = std::max(upper_indicator_y, upper_shared_y);
+ExtendedMouseWarpController::CreateWarpRegion(const gfx::Display& a,
+                                              const gfx::Display& b,
+                                              int64_t drag_source_id) {
+  gfx::Rect a_edge;
+  gfx::Rect b_edge;
+  int snap_barrier = drag_source_id == gfx::Display::kInvalidDisplayID
+                         ? 0
+                         : kMaximumSnapHeight;
+
+  if (!ComputeBoundary(a, b, &a_edge, &b_edge))
+    return nullptr;
+
+  // Creates the snap window barrirer only when horizontally connected.
+  if (a_edge.height() > a_edge.width()) {
+    if (drag_source_id == a.id())
+      AdjustSourceEdgeBounds(a.bounds(), snap_barrier, &a_edge);
+    else if (drag_source_id == b.id())
+      AdjustSourceEdgeBounds(b.bounds(), snap_barrier, &b_edge);
   }
-  a_indicator_bounds.set_y(upper_indicator_y);
-  a_indicator_bounds.set_height(lower_indicator_y - upper_indicator_y);
 
-  return make_scoped_ptr(
-      new WarpRegion(a.id(), b.id(), a_indicator_bounds, b_indicator_bounds));
+  return make_scoped_ptr(new WarpRegion(a.id(), b.id(), a_edge, b_edge));
 }
 
 }  // namespace ash
diff --git a/ash/display/extended_mouse_warp_controller.h b/ash/display/extended_mouse_warp_controller.h
index fa65eed..1126ef3 100644
--- a/ash/display/extended_mouse_warp_controller.h
+++ b/ash/display/extended_mouse_warp_controller.h
@@ -42,17 +42,16 @@ class ASH_EXPORT ExtendedMouseWarpController : public MouseWarpController {
 
  private:
   friend class test::DisplayManagerTestApi;
+  friend class ExtendedMouseWarpControllerTest;
   FRIEND_TEST_ALL_PREFIXES(ExtendedMouseWarpControllerTest,
-                           IndicatorBoundsTestOnRight);
-  FRIEND_TEST_ALL_PREFIXES(ExtendedMouseWarpControllerTest,
-                           IndicatorBoundsTestOnLeft);
+                           IndicatorBoundsTestThreeDisplays);
   FRIEND_TEST_ALL_PREFIXES(ExtendedMouseWarpControllerTest,
-                           IndicatorBoundsTestOnTopBottom);
+                           IndicatorBoundsTestThreeDisplaysWithLayout);
   FRIEND_TEST_ALL_PREFIXES(ExtendedMouseWarpControllerTest,
-                           IndicatorBoundsTestThreeDisplays);
+                           IndicatorBoundsTestThreeDisplaysWithLayout2);
 
   // Defined in header file because tests need access.
-  class WarpRegion {
+  class ASH_EXPORT WarpRegion {
    public:
     WarpRegion(int64_t a_display_id,
                int64_t b_display_id,
@@ -63,6 +62,8 @@ class ASH_EXPORT ExtendedMouseWarpController : public MouseWarpController {
     const gfx::Rect& a_indicator_bounds() { return a_indicator_bounds_; }
     const gfx::Rect& b_indicator_bounds() { return b_indicator_bounds_; }
 
+    const gfx::Rect& GetIndicatorBoundsForTest(int64_t id) const;
+
    private:
     friend class ExtendedMouseWarpController;
 
@@ -104,16 +105,14 @@ class ASH_EXPORT ExtendedMouseWarpController : public MouseWarpController {
                                      const gfx::Point& point_in_screen,
                                      bool update_mouse_location_now);
 
-  // Update the edge/indicator bounds based on the current
-  // display configuration.
-  scoped_ptr<WarpRegion> CreateHorizontalEdgeBounds(
-      const gfx::Display& a,
-      const gfx::Display& b,
-      DisplayPlacement::Position position);
-  scoped_ptr<WarpRegion> CreateVerticalEdgeBounds(
-      const gfx::Display& a,
-      const gfx::Display& b,
-      DisplayPlacement::Position position);
+  // Creates WarpRegion between display |a| and
+  // |b|. |drag_source_dispaly_id| is used to indicate in which
+  // display a drag is started, or invalid id passed if this is not
+  // for dragging. Returns null scoped_ptr if two displays do not
+  // share the edge.
+  scoped_ptr<WarpRegion> CreateWarpRegion(const gfx::Display& a,
+                                          const gfx::Display& b,
+                                          int64_t drag_source_dispay_id);
 
   void allow_non_native_event_for_test() { allow_non_native_event_ = true; }
 
diff --git a/ash/display/extended_mouse_warp_controller_unittest.cc b/ash/display/extended_mouse_warp_controller_unittest.cc
index 13f5e02..85988cc 100644
--- a/ash/display/extended_mouse_warp_controller_unittest.cc
+++ b/ash/display/extended_mouse_warp_controller_unittest.cc
@@ -4,6 +4,7 @@
 
 #include "ash/display/extended_mouse_warp_controller.h"
 
+#include "ash/display/display_layout_builder.h"
 #include "ash/display/display_layout_store.h"
 #include "ash/display/display_manager.h"
 #include "ash/display/mouse_cursor_event_filter.h"
@@ -31,6 +32,18 @@ class ExtendedMouseWarpControllerTest : public test::AshTestBase {
         event_filter()->mouse_warp_controller_for_test());
   }
 
+  size_t GetWarpRegionsCount() {
+    return mouse_warp_controller()->warp_regions_.size();
+  }
+
+  const ExtendedMouseWarpController::WarpRegion* GetWarpRegion(size_t index) {
+    return mouse_warp_controller()->warp_regions_[index].get();
+  }
+
+  const gfx::Rect& GetIndicatorBounds(int64_t id) {
+    return GetWarpRegion(0)->GetIndicatorBoundsForTest(id);
+  }
+
  private:
   DISALLOW_COPY_AND_ASSIGN(ExtendedMouseWarpControllerTest);
 };
@@ -42,23 +55,25 @@ TEST_F(ExtendedMouseWarpControllerTest, IndicatorBoundsTestOnRight) {
 
   UpdateDisplay("360x360,700x700");
   aura::Window::Windows root_windows = Shell::GetAllRootWindows();
+  int64_t display_0_id =
+      gfx::Screen::GetScreen()->GetDisplayNearestWindow(root_windows[0]).id();
+  int64_t display_1_id =
+      gfx::Screen::GetScreen()->GetDisplayNearestWindow(root_windows[1]).id();
 
   DisplayManager* display_manager = Shell::GetInstance()->display_manager();
   scoped_ptr<DisplayLayout> layout(
       test::CreateDisplayLayout(DisplayPlacement::RIGHT, 0));
+
   display_manager->SetLayoutForCurrentDisplays(layout->Copy());
   event_filter()->ShowSharedEdgeIndicator(root_windows[0] /* primary */);
 
-  ASSERT_EQ(1U, mouse_warp_controller()->warp_regions_.size());
-  EXPECT_EQ(gfx::Rect(359, 16, 1, 344),
-            mouse_warp_controller()->warp_regions_[0]->a_indicator_bounds());
-  EXPECT_EQ(gfx::Rect(360, 0, 1, 360),
-            mouse_warp_controller()->warp_regions_[0]->b_indicator_bounds());
+  ASSERT_EQ(1U, GetWarpRegionsCount());
+  EXPECT_EQ(gfx::Rect(359, 16, 1, 344), GetIndicatorBounds(display_0_id));
+  EXPECT_EQ(gfx::Rect(360, 0, 1, 360), GetIndicatorBounds(display_1_id));
+
   event_filter()->ShowSharedEdgeIndicator(root_windows[1] /* secondary */);
-  EXPECT_EQ(gfx::Rect(360, 16, 1, 344),
-            mouse_warp_controller()->warp_regions_[0]->a_indicator_bounds());
-  EXPECT_EQ(gfx::Rect(359, 0, 1, 360),
-            mouse_warp_controller()->warp_regions_[0]->b_indicator_bounds());
+  EXPECT_EQ(gfx::Rect(359, 0, 1, 360), GetIndicatorBounds(display_0_id));
+  EXPECT_EQ(gfx::Rect(360, 16, 1, 344), GetIndicatorBounds(display_1_id));
 
   // Move 2nd display downwards a bit.
   layout->placement_list[0].offset = 5;
@@ -66,51 +81,41 @@ TEST_F(ExtendedMouseWarpControllerTest, IndicatorBoundsTestOnRight) {
   event_filter()->ShowSharedEdgeIndicator(root_windows[0] /* primary */);
   // This is same as before because the 2nd display's y is above
   // the indicator's x.
-  ASSERT_EQ(1U, mouse_warp_controller()->warp_regions_.size());
-  EXPECT_EQ(gfx::Rect(359, 16, 1, 344),
-            mouse_warp_controller()->warp_regions_[0]->a_indicator_bounds());
-  EXPECT_EQ(gfx::Rect(360, 5, 1, 355),
-            mouse_warp_controller()->warp_regions_[0]->b_indicator_bounds());
+  ASSERT_EQ(1U, GetWarpRegionsCount());
+  EXPECT_EQ(gfx::Rect(359, 16, 1, 344), GetIndicatorBounds(display_0_id));
+  EXPECT_EQ(gfx::Rect(360, 5, 1, 355), GetIndicatorBounds(display_1_id));
+
   event_filter()->ShowSharedEdgeIndicator(root_windows[1] /* secondary */);
-  EXPECT_EQ(gfx::Rect(360, 21, 1, 339),
-            mouse_warp_controller()->warp_regions_[0]->a_indicator_bounds());
-  EXPECT_EQ(gfx::Rect(359, 5, 1, 355),
-            mouse_warp_controller()->warp_regions_[0]->b_indicator_bounds());
+  EXPECT_EQ(gfx::Rect(359, 5, 1, 355), GetIndicatorBounds(display_0_id));
+  EXPECT_EQ(gfx::Rect(360, 21, 1, 339), GetIndicatorBounds(display_1_id));
 
   // Move it down further so that the shared edge is shorter than
   // minimum hole size (160).
   layout->placement_list[0].offset = 200;
   display_manager->SetLayoutForCurrentDisplays(layout->Copy());
   event_filter()->ShowSharedEdgeIndicator(root_windows[0] /* primary */);
-  ASSERT_EQ(1U, mouse_warp_controller()->warp_regions_.size());
-  EXPECT_EQ(gfx::Rect(359, 200, 1, 160),
-            mouse_warp_controller()->warp_regions_[0]->a_indicator_bounds());
-  EXPECT_EQ(gfx::Rect(360, 200, 1, 160),
-            mouse_warp_controller()->warp_regions_[0]->b_indicator_bounds());
+  ASSERT_EQ(1U, GetWarpRegionsCount());
+  EXPECT_EQ(gfx::Rect(359, 200, 1, 160), GetIndicatorBounds(display_0_id));
+  EXPECT_EQ(gfx::Rect(360, 200, 1, 160), GetIndicatorBounds(display_1_id));
+
   event_filter()->ShowSharedEdgeIndicator(root_windows[1] /* secondary */);
-  ASSERT_EQ(1U, mouse_warp_controller()->warp_regions_.size());
-  EXPECT_EQ(gfx::Rect(360, 200, 1, 160),
-            mouse_warp_controller()->warp_regions_[0]->a_indicator_bounds());
-  EXPECT_EQ(gfx::Rect(359, 200, 1, 160),
-            mouse_warp_controller()->warp_regions_[0]->b_indicator_bounds());
+  ASSERT_EQ(1U, GetWarpRegionsCount());
+  EXPECT_EQ(gfx::Rect(359, 200, 1, 160), GetIndicatorBounds(display_0_id));
+  EXPECT_EQ(gfx::Rect(360, 200, 1, 160), GetIndicatorBounds(display_1_id));
 
   // Now move 2nd display upwards
   layout->placement_list[0].offset = -5;
   display_manager->SetLayoutForCurrentDisplays(layout->Copy());
   event_filter()->ShowSharedEdgeIndicator(root_windows[0] /* primary */);
-  ASSERT_EQ(1U, mouse_warp_controller()->warp_regions_.size());
-  EXPECT_EQ(gfx::Rect(359, 16, 1, 344),
-            mouse_warp_controller()->warp_regions_[0]->a_indicator_bounds());
-  EXPECT_EQ(gfx::Rect(360, 0, 1, 360),
-            mouse_warp_controller()->warp_regions_[0]->b_indicator_bounds());
+  ASSERT_EQ(1U, GetWarpRegionsCount());
+  EXPECT_EQ(gfx::Rect(359, 16, 1, 344), GetIndicatorBounds(display_0_id));
+  EXPECT_EQ(gfx::Rect(360, 0, 1, 360), GetIndicatorBounds(display_1_id));
   event_filter()->ShowSharedEdgeIndicator(root_windows[1] /* secondary */);
   // 16 px are reserved on 2nd display from top, so y must be
   // (16 - 5) = 11
-  ASSERT_EQ(1U, mouse_warp_controller()->warp_regions_.size());
-  EXPECT_EQ(gfx::Rect(360, 11, 1, 349),
-            mouse_warp_controller()->warp_regions_[0]->a_indicator_bounds());
-  EXPECT_EQ(gfx::Rect(359, 0, 1, 360),
-            mouse_warp_controller()->warp_regions_[0]->b_indicator_bounds());
+  ASSERT_EQ(1U, GetWarpRegionsCount());
+  EXPECT_EQ(gfx::Rect(359, 0, 1, 360), GetIndicatorBounds(display_0_id));
+  EXPECT_EQ(gfx::Rect(360, 11, 1, 349), GetIndicatorBounds(display_1_id));
 
   event_filter()->HideSharedEdgeIndicator();
 }
@@ -122,37 +127,38 @@ TEST_F(ExtendedMouseWarpControllerTest, IndicatorBoundsTestOnLeft) {
   UpdateDisplay("360x360,700x700");
   aura::Window::Windows root_windows = Shell::GetAllRootWindows();
 
+  int64_t display_0_id =
+      gfx::Screen::GetScreen()->GetDisplayNearestWindow(root_windows[0]).id();
+  int64_t display_1_id =
+      gfx::Screen::GetScreen()->GetDisplayNearestWindow(root_windows[1]).id();
+
   DisplayManager* display_manager = Shell::GetInstance()->display_manager();
   scoped_ptr<DisplayLayout> layout(
       test::CreateDisplayLayout(DisplayPlacement::LEFT, 0));
   display_manager->SetLayoutForCurrentDisplays(layout->Copy());
+
   event_filter()->ShowSharedEdgeIndicator(root_windows[0] /* primary */);
-  ASSERT_EQ(1U, mouse_warp_controller()->warp_regions_.size());
-  EXPECT_EQ(gfx::Rect(0, 16, 1, 344),
-            mouse_warp_controller()->warp_regions_[0]->a_indicator_bounds());
-  EXPECT_EQ(gfx::Rect(-1, 0, 1, 360),
-            mouse_warp_controller()->warp_regions_[0]->b_indicator_bounds());
+  ASSERT_EQ(1U, GetWarpRegionsCount());
+  EXPECT_EQ(gfx::Rect(0, 16, 1, 344), GetIndicatorBounds(display_0_id));
+  EXPECT_EQ(gfx::Rect(-1, 0, 1, 360), GetIndicatorBounds(display_1_id));
+
   event_filter()->ShowSharedEdgeIndicator(root_windows[1] /* secondary */);
-  ASSERT_EQ(1U, mouse_warp_controller()->warp_regions_.size());
-  EXPECT_EQ(gfx::Rect(-1, 16, 1, 344),
-            mouse_warp_controller()->warp_regions_[0]->a_indicator_bounds());
-  EXPECT_EQ(gfx::Rect(0, 0, 1, 360),
-            mouse_warp_controller()->warp_regions_[0]->b_indicator_bounds());
+  ASSERT_EQ(1U, GetWarpRegionsCount());
+  EXPECT_EQ(gfx::Rect(0, 0, 1, 360), GetIndicatorBounds(display_0_id));
+  EXPECT_EQ(gfx::Rect(-1, 16, 1, 344), GetIndicatorBounds(display_1_id));
 
   layout->placement_list[0].offset = 250;
   display_manager->SetLayoutForCurrentDisplays(layout->Copy());
   event_filter()->ShowSharedEdgeIndicator(root_windows[0] /* primary */);
-  ASSERT_EQ(1U, mouse_warp_controller()->warp_regions_.size());
-  EXPECT_EQ(gfx::Rect(0, 250, 1, 110),
-            mouse_warp_controller()->warp_regions_[0]->a_indicator_bounds());
-  EXPECT_EQ(gfx::Rect(-1, 250, 1, 110),
-            mouse_warp_controller()->warp_regions_[0]->b_indicator_bounds());
+  ASSERT_EQ(1U, GetWarpRegionsCount());
+  EXPECT_EQ(gfx::Rect(0, 250, 1, 110), GetIndicatorBounds(display_0_id));
+  EXPECT_EQ(gfx::Rect(-1, 250, 1, 110), GetIndicatorBounds(display_1_id));
+
   event_filter()->ShowSharedEdgeIndicator(root_windows[1] /* secondary */);
-  ASSERT_EQ(1U, mouse_warp_controller()->warp_regions_.size());
-  EXPECT_EQ(gfx::Rect(-1, 250, 1, 110),
-            mouse_warp_controller()->warp_regions_[0]->a_indicator_bounds());
-  EXPECT_EQ(gfx::Rect(0, 250, 1, 110),
-            mouse_warp_controller()->warp_regions_[0]->b_indicator_bounds());
+  ASSERT_EQ(1U, GetWarpRegionsCount());
+  EXPECT_EQ(gfx::Rect(0, 250, 1, 110), GetIndicatorBounds(display_0_id));
+  EXPECT_EQ(gfx::Rect(-1, 250, 1, 110), GetIndicatorBounds(display_1_id));
+
   event_filter()->HideSharedEdgeIndicator();
 }
 
@@ -162,54 +168,49 @@ TEST_F(ExtendedMouseWarpControllerTest, IndicatorBoundsTestOnTopBottom) {
 
   UpdateDisplay("360x360,700x700");
   aura::Window::Windows root_windows = Shell::GetAllRootWindows();
+  int64_t display_0_id =
+      gfx::Screen::GetScreen()->GetDisplayNearestWindow(root_windows[0]).id();
+  int64_t display_1_id =
+      gfx::Screen::GetScreen()->GetDisplayNearestWindow(root_windows[1]).id();
 
   DisplayManager* display_manager = Shell::GetInstance()->display_manager();
   scoped_ptr<DisplayLayout> layout(
       test::CreateDisplayLayout(DisplayPlacement::TOP, 0));
   display_manager->SetLayoutForCurrentDisplays(layout->Copy());
   event_filter()->ShowSharedEdgeIndicator(root_windows[0] /* primary */);
-  ASSERT_EQ(1U, mouse_warp_controller()->warp_regions_.size());
-  EXPECT_EQ(gfx::Rect(0, 0, 360, 1),
-            mouse_warp_controller()->warp_regions_[0]->a_indicator_bounds());
-  EXPECT_EQ(gfx::Rect(0, -1, 360, 1),
-            mouse_warp_controller()->warp_regions_[0]->b_indicator_bounds());
+  ASSERT_EQ(1U, GetWarpRegionsCount());
+  EXPECT_EQ(gfx::Rect(0, 0, 360, 1), GetIndicatorBounds(display_0_id));
+  EXPECT_EQ(gfx::Rect(0, -1, 360, 1), GetIndicatorBounds(display_1_id));
+
   event_filter()->ShowSharedEdgeIndicator(root_windows[1] /* secondary */);
-  ASSERT_EQ(1U, mouse_warp_controller()->warp_regions_.size());
-  EXPECT_EQ(gfx::Rect(0, -1, 360, 1),
-            mouse_warp_controller()->warp_regions_[0]->a_indicator_bounds());
-  EXPECT_EQ(gfx::Rect(0, 0, 360, 1),
-            mouse_warp_controller()->warp_regions_[0]->b_indicator_bounds());
+  ASSERT_EQ(1U, GetWarpRegionsCount());
+  EXPECT_EQ(gfx::Rect(0, 0, 360, 1), GetIndicatorBounds(display_0_id));
+  EXPECT_EQ(gfx::Rect(0, -1, 360, 1), GetIndicatorBounds(display_1_id));
 
   layout->placement_list[0].offset = 250;
   display_manager->SetLayoutForCurrentDisplays(layout->Copy());
   event_filter()->ShowSharedEdgeIndicator(root_windows[0] /* primary */);
-  ASSERT_EQ(1U, mouse_warp_controller()->warp_regions_.size());
-  EXPECT_EQ(gfx::Rect(250, 0, 110, 1),
-            mouse_warp_controller()->warp_regions_[0]->a_indicator_bounds());
-  EXPECT_EQ(gfx::Rect(250, -1, 110, 1),
-            mouse_warp_controller()->warp_regions_[0]->b_indicator_bounds());
+  ASSERT_EQ(1U, GetWarpRegionsCount());
+  EXPECT_EQ(gfx::Rect(250, 0, 110, 1), GetIndicatorBounds(display_0_id));
+  EXPECT_EQ(gfx::Rect(250, -1, 110, 1), GetIndicatorBounds(display_1_id));
+
   event_filter()->ShowSharedEdgeIndicator(root_windows[1] /* secondary */);
-  ASSERT_EQ(1U, mouse_warp_controller()->warp_regions_.size());
-  EXPECT_EQ(gfx::Rect(250, -1, 110, 1),
-            mouse_warp_controller()->warp_regions_[0]->a_indicator_bounds());
-  EXPECT_EQ(gfx::Rect(250, 0, 110, 1),
-            mouse_warp_controller()->warp_regions_[0]->b_indicator_bounds());
+  ASSERT_EQ(1U, GetWarpRegionsCount());
+  EXPECT_EQ(gfx::Rect(250, 0, 110, 1), GetIndicatorBounds(display_0_id));
+  EXPECT_EQ(gfx::Rect(250, -1, 110, 1), GetIndicatorBounds(display_1_id));
 
   layout->placement_list[0].position = DisplayPlacement::BOTTOM;
   layout->placement_list[0].offset = 0;
   display_manager->SetLayoutForCurrentDisplays(layout->Copy());
   event_filter()->ShowSharedEdgeIndicator(root_windows[0] /* primary */);
-  ASSERT_EQ(1U, mouse_warp_controller()->warp_regions_.size());
-  EXPECT_EQ(gfx::Rect(0, 359, 360, 1),
-            mouse_warp_controller()->warp_regions_[0]->a_indicator_bounds());
-  EXPECT_EQ(gfx::Rect(0, 360, 360, 1),
-            mouse_warp_controller()->warp_regions_[0]->b_indicator_bounds());
+  ASSERT_EQ(1U, GetWarpRegionsCount());
+  EXPECT_EQ(gfx::Rect(0, 359, 360, 1), GetIndicatorBounds(display_0_id));
+  EXPECT_EQ(gfx::Rect(0, 360, 360, 1), GetIndicatorBounds(display_1_id));
+
   event_filter()->ShowSharedEdgeIndicator(root_windows[1] /* secondary */);
-  ASSERT_EQ(1U, mouse_warp_controller()->warp_regions_.size());
-  EXPECT_EQ(gfx::Rect(0, 360, 360, 1),
-            mouse_warp_controller()->warp_regions_[0]->a_indicator_bounds());
-  EXPECT_EQ(gfx::Rect(0, 359, 360, 1),
-            mouse_warp_controller()->warp_regions_[0]->b_indicator_bounds());
+  ASSERT_EQ(1U, GetWarpRegionsCount());
+  EXPECT_EQ(gfx::Rect(0, 359, 360, 1), GetIndicatorBounds(display_0_id));
+  EXPECT_EQ(gfx::Rect(0, 360, 360, 1), GetIndicatorBounds(display_1_id));
 
   event_filter()->HideSharedEdgeIndicator();
 }
@@ -219,52 +220,152 @@ TEST_F(ExtendedMouseWarpControllerTest, IndicatorBoundsTestThreeDisplays) {
   if (!SupportsMultipleDisplays())
     return;
 
-  auto run_test = [this] {
-    aura::Window::Windows root_windows = Shell::GetAllRootWindows();
-
-    // Left most display
-    event_filter()->ShowSharedEdgeIndicator(root_windows[0]);
-    ASSERT_EQ(2U, mouse_warp_controller()->warp_regions_.size());
-    EXPECT_EQ(gfx::Rect(359, 16, 1, 344),
-              mouse_warp_controller()->warp_regions_[0]->a_indicator_bounds());
-    EXPECT_EQ(gfx::Rect(360, 0, 1, 360),
-              mouse_warp_controller()->warp_regions_[0]->b_indicator_bounds());
-    EXPECT_EQ(gfx::Rect(1060, 16, 1, 684),
-              mouse_warp_controller()->warp_regions_[1]->a_indicator_bounds());
-    EXPECT_EQ(gfx::Rect(1059, 0, 1, 700),
-              mouse_warp_controller()->warp_regions_[1]->b_indicator_bounds());
-
-    // Middle display
-    event_filter()->ShowSharedEdgeIndicator(root_windows[1]);
-    ASSERT_EQ(2U, mouse_warp_controller()->warp_regions_.size());
-    EXPECT_EQ(gfx::Rect(360, 16, 1, 344),
-              mouse_warp_controller()->warp_regions_[0]->a_indicator_bounds());
-    EXPECT_EQ(gfx::Rect(359, 0, 1, 360),
-              mouse_warp_controller()->warp_regions_[0]->b_indicator_bounds());
-    EXPECT_EQ(gfx::Rect(1059, 16, 1, 684),
-              mouse_warp_controller()->warp_regions_[1]->a_indicator_bounds());
-    EXPECT_EQ(gfx::Rect(1060, 0, 1, 700),
-              mouse_warp_controller()->warp_regions_[1]->b_indicator_bounds());
-
-    // Right most display
-    event_filter()->ShowSharedEdgeIndicator(root_windows[2]);
-    ASSERT_EQ(2U, mouse_warp_controller()->warp_regions_.size());
-    EXPECT_EQ(gfx::Rect(360, 16, 1, 344),
-              mouse_warp_controller()->warp_regions_[0]->a_indicator_bounds());
-    EXPECT_EQ(gfx::Rect(359, 0, 1, 360),
-              mouse_warp_controller()->warp_regions_[0]->b_indicator_bounds());
-    EXPECT_EQ(gfx::Rect(1060, 16, 1, 684),
-              mouse_warp_controller()->warp_regions_[1]->a_indicator_bounds());
-    EXPECT_EQ(gfx::Rect(1059, 0, 1, 700),
-              mouse_warp_controller()->warp_regions_[1]->b_indicator_bounds());
-
-    event_filter()->HideSharedEdgeIndicator();
-  };
-
   UpdateDisplay("360x360,700x700,1000x1000");
-  run_test();
+  aura::Window::Windows root_windows = Shell::GetAllRootWindows();
+  gfx::Screen* screen = gfx::Screen::GetScreen();
+  int64_t display_0_id = screen->GetDisplayNearestWindow(root_windows[0]).id();
+  int64_t display_1_id = screen->GetDisplayNearestWindow(root_windows[1]).id();
+  int64_t display_2_id = screen->GetDisplayNearestWindow(root_windows[2]).id();
+
+  // Drag from left most display
+  event_filter()->ShowSharedEdgeIndicator(root_windows[0]);
+  ASSERT_EQ(2U, GetWarpRegionsCount());
+  const ExtendedMouseWarpController::WarpRegion* region_0 = GetWarpRegion(0);
+  const ExtendedMouseWarpController::WarpRegion* region_1 = GetWarpRegion(1);
+  EXPECT_EQ(gfx::Rect(359, 16, 1, 344),
+            region_1->GetIndicatorBoundsForTest(display_0_id));
+  EXPECT_EQ(gfx::Rect(360, 0, 1, 360),
+            region_1->GetIndicatorBoundsForTest(display_1_id));
+  EXPECT_EQ(gfx::Rect(1059, 0, 1, 700),
+            region_0->GetIndicatorBoundsForTest(display_1_id));
+  EXPECT_EQ(gfx::Rect(1060, 0, 1, 700),
+            region_0->GetIndicatorBoundsForTest(display_2_id));
+
+  // Drag from middle display
+  event_filter()->ShowSharedEdgeIndicator(root_windows[1]);
+  ASSERT_EQ(2U, mouse_warp_controller()->warp_regions_.size());
+  region_0 = GetWarpRegion(0);
+  region_1 = GetWarpRegion(1);
+  EXPECT_EQ(gfx::Rect(359, 0, 1, 360),
+            region_1->GetIndicatorBoundsForTest(display_0_id));
+  EXPECT_EQ(gfx::Rect(360, 16, 1, 344),
+            region_1->GetIndicatorBoundsForTest(display_1_id));
+  EXPECT_EQ(gfx::Rect(1059, 16, 1, 684),
+            region_0->GetIndicatorBoundsForTest(display_1_id));
+  EXPECT_EQ(gfx::Rect(1060, 0, 1, 700),
+            region_0->GetIndicatorBoundsForTest(display_2_id));
+
+  // Right most display
+  event_filter()->ShowSharedEdgeIndicator(root_windows[2]);
+  ASSERT_EQ(2U, mouse_warp_controller()->warp_regions_.size());
+  region_0 = GetWarpRegion(0);
+  region_1 = GetWarpRegion(1);
+  EXPECT_EQ(gfx::Rect(359, 0, 1, 360),
+            region_1->GetIndicatorBoundsForTest(display_0_id));
+  EXPECT_EQ(gfx::Rect(360, 0, 1, 360),
+            region_1->GetIndicatorBoundsForTest(display_1_id));
+  EXPECT_EQ(gfx::Rect(1059, 0, 1, 700),
+            region_0->GetIndicatorBoundsForTest(display_1_id));
+  EXPECT_EQ(gfx::Rect(1060, 16, 1, 684),
+            region_0->GetIndicatorBoundsForTest(display_2_id));
+  event_filter()->HideSharedEdgeIndicator();
+  // TODO(oshima): Add test cases primary swap.
+}
 
-  // TODO(oshima): Add test cases with layouts, primary swap.
+TEST_F(ExtendedMouseWarpControllerTest,
+       IndicatorBoundsTestThreeDisplaysWithLayout) {
+  if (!SupportsMultipleDisplays())
+    return;
+  UpdateDisplay("700x500,500x500,1000x1000");
+  aura::Window::Windows root_windows = Shell::GetAllRootWindows();
+  gfx::Screen* screen = gfx::Screen::GetScreen();
+  int64_t display_0_id = screen->GetDisplayNearestWindow(root_windows[0]).id();
+  int64_t display_1_id = screen->GetDisplayNearestWindow(root_windows[1]).id();
+  int64_t display_2_id = screen->GetDisplayNearestWindow(root_windows[2]).id();
+
+  // Layout so that all displays touches togter like this:
+  //  +-----+---+
+  //  |  0  | 1 |
+  //  +-+---+--++
+  //    |  2   |
+  //    +------+
+  ash::DisplayLayoutBuilder builder(display_0_id);
+  builder.AddDisplayPlacement(display_1_id, display_0_id,
+                              ash::DisplayPlacement::RIGHT, 0);
+  builder.AddDisplayPlacement(display_2_id, display_0_id,
+                              ash::DisplayPlacement::BOTTOM, 100);
+
+  DisplayManager* display_manager = Shell::GetInstance()->display_manager();
+  display_manager->SetLayoutForCurrentDisplays(builder.Build());
+  ASSERT_EQ(3U, GetWarpRegionsCount());
+
+  // Drag from 0.
+  event_filter()->ShowSharedEdgeIndicator(root_windows[0]);
+  ASSERT_EQ(3U, GetWarpRegionsCount());
+  const ExtendedMouseWarpController::WarpRegion* region_0 = GetWarpRegion(0);
+  const ExtendedMouseWarpController::WarpRegion* region_1 = GetWarpRegion(1);
+  const ExtendedMouseWarpController::WarpRegion* region_2 = GetWarpRegion(2);
+  // between 2 and 0
+  EXPECT_EQ(gfx::Rect(100, 499, 600, 1),
+            region_0->GetIndicatorBoundsForTest(display_0_id));
+  EXPECT_EQ(gfx::Rect(100, 500, 600, 1),
+            region_0->GetIndicatorBoundsForTest(display_2_id));
+  // between 2 and 1
+  EXPECT_EQ(gfx::Rect(700, 499, 400, 1),
+            region_1->GetIndicatorBoundsForTest(display_1_id));
+  EXPECT_EQ(gfx::Rect(700, 500, 400, 1),
+            region_1->GetIndicatorBoundsForTest(display_2_id));
+  // between 1 and 0
+  EXPECT_EQ(gfx::Rect(699, 16, 1, 484),
+            region_2->GetIndicatorBoundsForTest(display_0_id));
+  EXPECT_EQ(gfx::Rect(700, 0, 1, 500),
+            region_2->GetIndicatorBoundsForTest(display_1_id));
+  event_filter()->HideSharedEdgeIndicator();
+}
+
+TEST_F(ExtendedMouseWarpControllerTest,
+       IndicatorBoundsTestThreeDisplaysWithLayout2) {
+  if (!SupportsMultipleDisplays())
+    return;
+  UpdateDisplay("700x500,500x500,1000x1000");
+  aura::Window::Windows root_windows = Shell::GetAllRootWindows();
+  gfx::Screen* screen = gfx::Screen::GetScreen();
+  int64_t display_0_id = screen->GetDisplayNearestWindow(root_windows[0]).id();
+  int64_t display_1_id = screen->GetDisplayNearestWindow(root_windows[1]).id();
+  int64_t display_2_id = screen->GetDisplayNearestWindow(root_windows[2]).id();
+
+  // Layout so that 0 and 1 displays are disconnected.
+  //  +-----+ +---+
+  //  |  0  | |1 |
+  //  +-+---+-+++
+  //    |  2   |
+  //    +------+
+  ash::DisplayLayoutBuilder builder(display_0_id);
+  builder.AddDisplayPlacement(display_2_id, display_0_id,
+                              ash::DisplayPlacement::BOTTOM, 100);
+  builder.AddDisplayPlacement(display_1_id, display_2_id,
+                              ash::DisplayPlacement::TOP, 800);
+
+  DisplayManager* display_manager = Shell::GetInstance()->display_manager();
+  display_manager->SetLayoutForCurrentDisplays(builder.Build());
+  ASSERT_EQ(2U, GetWarpRegionsCount());
+
+  // Drag from 0.
+  event_filter()->ShowSharedEdgeIndicator(root_windows[0]);
+  ASSERT_EQ(2U, GetWarpRegionsCount());
+  const ExtendedMouseWarpController::WarpRegion* region_0 = GetWarpRegion(0);
+  const ExtendedMouseWarpController::WarpRegion* region_1 = GetWarpRegion(1);
+  // between 2 and 0
+  EXPECT_EQ(gfx::Rect(100, 499, 600, 1),
+            region_0->GetIndicatorBoundsForTest(display_0_id));
+  EXPECT_EQ(gfx::Rect(100, 500, 600, 1),
+            region_0->GetIndicatorBoundsForTest(display_2_id));
+  // between 2 and 1
+  EXPECT_EQ(gfx::Rect(900, 499, 200, 1),
+            region_1->GetIndicatorBoundsForTest(display_1_id));
+  EXPECT_EQ(gfx::Rect(900, 500, 200, 1),
+            region_1->GetIndicatorBoundsForTest(display_2_id));
+  event_filter()->HideSharedEdgeIndicator();
 }
 
 }  // namespace ash
diff --git a/ash/display/unified_mouse_warp_controller.cc b/ash/display/unified_mouse_warp_controller.cc
index 267f2f5..fec9b60 100644
--- a/ash/display/unified_mouse_warp_controller.cc
+++ b/ash/display/unified_mouse_warp_controller.cc
@@ -131,8 +131,9 @@ void UnifiedMouseWarpController::ComputeBounds() {
 
   const gfx::Display& first = display_list[0];
   const gfx::Display& second = display_list[1];
-  ComputeBoundary(first, second, &first_edge_bounds_in_native_,
-                  &second_edge_bounds_in_native_);
+  bool success = ComputeBoundary(first, second, &first_edge_bounds_in_native_,
+                                 &second_edge_bounds_in_native_);
+  DCHECK(success);
 
   first_edge_bounds_in_native_ =
       GetNativeEdgeBounds(GetMirroringAshWindowTreeHostForDisplayId(first.id()),
diff --git a/chrome/browser/chromeos/display/display_preferences.cc b/chrome/browser/chromeos/display/display_preferences.cc
index bb2a063..646cc95 100644
--- a/chrome/browser/chromeos/display/display_preferences.cc
+++ b/chrome/browser/chromeos/display/display_preferences.cc
@@ -127,17 +127,15 @@ void LoadDisplayLayouts() {
     if (it.key().find(",") != std::string::npos) {
       std::vector<std::string> ids_str = base::SplitString(
           it.key(), ",", base::TRIM_WHITESPACE, base::SPLIT_WANT_ALL);
-      int64_t id1 = gfx::Display::kInvalidDisplayID;
-      int64_t id2 = gfx::Display::kInvalidDisplayID;
-      if (!base::StringToInt64(ids_str[0], &id1) ||
-          !base::StringToInt64(ids_str[1], &id2) ||
-          id1 == gfx::Display::kInvalidDisplayID ||
-          id2 == gfx::Display::kInvalidDisplayID) {
-        continue;
+      std::vector<int64_t> ids;
+      for (std::string id_str : ids_str) {
+        int64_t id;
+        if (!base::StringToInt64(id_str, &id))
+          continue;
+        ids.push_back(id);
       }
-      int64_t ids[] = {id1, id2};
       ash::DisplayIdList list =
-          ash::GenerateDisplayIdList(std::begin(ids), std::end(ids));
+          ash::GenerateDisplayIdList(ids.begin(), ids.end());
       layout_store->RegisterLayoutForDisplayIdList(list, std::move(layout));
     }
   }
diff --git a/chrome/browser/chromeos/display/display_preferences_unittest.cc b/chrome/browser/chromeos/display/display_preferences_unittest.cc
index 18f0d2a..297c286 100644
--- a/chrome/browser/chromeos/display/display_preferences_unittest.cc
+++ b/chrome/browser/chromeos/display/display_preferences_unittest.cc
@@ -1053,4 +1053,57 @@ TEST_F(DisplayPreferencesTest, RestoreUnifiedMode) {
   EXPECT_FALSE(display_manager->IsInUnifiedMode());
 }
 
+TEST_F(DisplayPreferencesTest, SaveThreeDisplays) {
+  LoggedInAsUser();
+  ash::DisplayManager* display_manager =
+      ash::Shell::GetInstance()->display_manager();
+  UpdateDisplay("200x200,200x200,300x300");
+
+  ash::DisplayIdList list = display_manager->GetCurrentDisplayIdList();
+  ASSERT_EQ(3u, list.size());
+
+  ash::DisplayLayoutBuilder builder(list[0]);
+  builder.AddDisplayPlacement(list[1], list[0], ash::DisplayPlacement::RIGHT,
+                              0);
+  builder.AddDisplayPlacement(list[2], list[0], ash::DisplayPlacement::BOTTOM,
+                              100);
+  display_manager->SetLayoutForCurrentDisplays(builder.Build());
+
+  const base::DictionaryValue* secondary_displays =
+      local_state()->GetDictionary(prefs::kSecondaryDisplays);
+  const base::DictionaryValue* new_value = nullptr;
+  EXPECT_TRUE(secondary_displays->GetDictionary(
+      ash::DisplayIdListToString(list), &new_value));
+}
+
+TEST_F(DisplayPreferencesTest, RestoreThreeDisplays) {
+  LoggedInAsUser();
+  ash::DisplayManager* display_manager =
+      ash::Shell::GetInstance()->display_manager();
+  int64_t id1 = gfx::Screen::GetScreen()->GetPrimaryDisplay().id();
+  ash::DisplayIdList list =
+      ash::test::CreateDisplayIdListN(3, id1, id1 + 1, id1 + 2);
+
+  ash::DisplayLayoutBuilder builder(list[0]);
+  builder.AddDisplayPlacement(list[1], list[0], ash::DisplayPlacement::LEFT, 0);
+  builder.AddDisplayPlacement(list[2], list[1], ash::DisplayPlacement::BOTTOM,
+                              100);
+  StoreDisplayLayoutPrefForTest(list, *builder.Build());
+  LoadDisplayPreferences(false);
+
+  UpdateDisplay("200x200,200x200,300x300");
+  ash::DisplayIdList new_list = display_manager->GetCurrentDisplayIdList();
+  ASSERT_EQ(3u, list.size());
+  ASSERT_EQ(list[0], new_list[0]);
+  ASSERT_EQ(list[1], new_list[1]);
+  ASSERT_EQ(list[2], new_list[2]);
+
+  EXPECT_EQ(gfx::Rect(0, 0, 200, 200),
+            display_manager->GetDisplayForId(list[0]).bounds());
+  EXPECT_EQ(gfx::Rect(-200, 0, 200, 200),
+            display_manager->GetDisplayForId(list[1]).bounds());
+  EXPECT_EQ(gfx::Rect(-100, 200, 300, 300),
+            display_manager->GetDisplayForId(list[2]).bounds());
+}
+
 }  // namespace chromeos