Revert of Adjusts dragging logic to be less likely to trigger false positive switch from snapping to docking (patchset #5 id:90001 of https://codereview.chromium.org/1127133003/)

Reason for revert:
I suspect this is causing a browser_tests failure on the bots:

http://build.chromium.org/p/chromium.chromiumos/builders/Linux%20ChromiumOS%20Tests%20%28dbg%29%281%29/builds/2069
https://build.chromium.org/p/chromium.webkit/builders/Linux%20ChromiumOS%20Tests%20%28dbg%29%281%29/builds/1913

Sorry!

Original issue's description:
> Adjusts dragging logic to be less likely to trigger false positive switch from
> snapping to docking.
>
> This CL adjusts the logic which selects whether a window will be snapped to
> half of the workspace width or will be docked at the end of the drag when the
> window is dragged to the edge of the workspace in the special case of the dock
> being visible. The CL makes it easier to snap a window to half the workspace
> width in this special case (and harder to inadvertently dock the window)
>
> BUG=484877
> TEST=None
>
> Committed: https://crrev.com/988c697aff35b3fd347dec35f2f2ac159c8328a9
> Cr-Commit-Position: refs/heads/master@{#329268}

TBR=pkotwicz@chromium.org,varkha@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=484877

Review URL: https://codereview.chromium.org/1128933005

Cr-Commit-Position: refs/heads/master@{#329301}

4 files changed, 25 insertions, 54 deletions

diff --git a/ash/wm/workspace/two_step_edge_cycler.cc b/ash/wm/workspace/two_step_edge_cycler.cc
index 7f1ba474..45bedeb 100644
--- a/ash/wm/workspace/two_step_edge_cycler.cc
+++ b/ash/wm/workspace/two_step_edge_cycler.cc
@@ -12,26 +12,20 @@ namespace {
 // We cycle to the second mode if any of the following happens while the mouse
 // is on the edge of the workspace:
 // . The user stops moving the mouse for |kMaxDelay| and then moves the mouse
-//   again in the preferred direction from the last paused location for at least
-//   |kMaxPixelsAfterPause| horizontal pixels.
-// . The mouse moves |kMaxPixels| horizontal pixels in the preferred direction.
-// . The mouse is moved |kMaxMoves| times since the last pause.
-const int kMaxDelay = 400;
+//   again.
+// . The mouse moves |kMaxPixels| horizontal pixels.
+// . The mouse is moved |kMaxMoves| times.
+const int kMaxDelay = 500;
 const int kMaxPixels = 100;
-const int kMaxPixelsAfterPause = 10;
 const int kMaxMoves = 25;
 
 }  // namespace
 
-TwoStepEdgeCycler::TwoStepEdgeCycler(const gfx::Point& start,
-                                     TwoStepEdgeCycler::Direction direction)
+TwoStepEdgeCycler::TwoStepEdgeCycler(const gfx::Point& start)
     : second_mode_(false),
       time_last_move_(base::TimeTicks::Now()),
       num_moves_(0),
-      start_x_(start.x()),
-      paused_x_(start.x()),
-      paused_(false),
-      direction_(direction) {
+      start_x_(start.x()) {
 }
 
 TwoStepEdgeCycler::~TwoStepEdgeCycler() {
@@ -41,25 +35,13 @@ void TwoStepEdgeCycler::OnMove(const gfx::Point& location) {
   if (second_mode_)
     return;
 
-  if ((base::TimeTicks::Now() - time_last_move_).InMilliseconds() > kMaxDelay) {
-    paused_ = true;
-    paused_x_ = location.x();
-    num_moves_ = 0;
-  }
-  time_last_move_ = base::TimeTicks::Now();
-
-  int compare_x = paused_ ? paused_x_ : start_x_;
-  if (location.x() != compare_x &&
-      (location.x() < compare_x) != (direction_ == DIRECTION_LEFT)) {
-    return;
-  }
-
   ++num_moves_;
-  bool moved_in_the_same_direction_after_pause =
-      paused_ && std::abs(location.x() - paused_x_) >= kMaxPixelsAfterPause;
-  second_mode_ = moved_in_the_same_direction_after_pause ||
-                 std::abs(location.x() - start_x_) >= kMaxPixels ||
-                 num_moves_ >= kMaxMoves;
+  second_mode_ =
+      (base::TimeTicks::Now() - time_last_move_).InMilliseconds() >
+          kMaxDelay ||
+      std::abs(location.x() - start_x_) >= kMaxPixels ||
+      num_moves_ >= kMaxMoves;
+  time_last_move_ = base::TimeTicks::Now();
 }
 
 }  // namespace ash
diff --git a/ash/wm/workspace/two_step_edge_cycler.h b/ash/wm/workspace/two_step_edge_cycler.h
index 3254cfd..01ca086 100644
--- a/ash/wm/workspace/two_step_edge_cycler.h
+++ b/ash/wm/workspace/two_step_edge_cycler.h
@@ -19,10 +19,7 @@ namespace ash {
 // the workspace.
 class ASH_EXPORT TwoStepEdgeCycler {
  public:
-  // The direction in which a mouse should travel to switch mode.
-  enum Direction { DIRECTION_LEFT, DIRECTION_RIGHT };
-
-  explicit TwoStepEdgeCycler(const gfx::Point& start, Direction direction);
+  explicit TwoStepEdgeCycler(const gfx::Point& start);
   ~TwoStepEdgeCycler();
 
   // Update which mode should be used as a result of a mouse / touch move.
@@ -44,15 +41,6 @@ class ASH_EXPORT TwoStepEdgeCycler {
   // Initial x-coordinate.
   int start_x_;
 
-  // x-coordinate when paused.
-  int paused_x_;
-
-  // Whether the movement was paused.
-  bool paused_;
-
-  // Determines a preferred movement direction that we are watching.
-  Direction direction_;
-
   DISALLOW_COPY_AND_ASSIGN(TwoStepEdgeCycler);
 };
 
diff --git a/ash/wm/workspace/workspace_window_resizer.cc b/ash/wm/workspace/workspace_window_resizer.cc
index 73ba6fb..bd1ef25 100644
--- a/ash/wm/workspace/workspace_window_resizer.cc
+++ b/ash/wm/workspace/workspace_window_resizer.cc
@@ -941,14 +941,10 @@ void WorkspaceWindowResizer::UpdateSnapPhantomWindow(const gfx::Point& location,
     edge_cycler_.reset();
     return;
   }
-  if (!edge_cycler_) {
-    edge_cycler_.reset(new TwoStepEdgeCycler(
-        location, snap_type_ == SNAP_LEFT
-                      ? TwoStepEdgeCycler::DIRECTION_LEFT
-                      : TwoStepEdgeCycler::DIRECTION_RIGHT));
-  } else {
+  if (!edge_cycler_)
+    edge_cycler_.reset(new TwoStepEdgeCycler(location));
+  else
     edge_cycler_->OnMove(location);
-  }
 
   // Update phantom window with snapped or docked guide bounds.
   // Windows that cannot be snapped or are less wide than kMaxDockWidth can get
diff --git a/ash/wm/workspace/workspace_window_resizer.h b/ash/wm/workspace/workspace_window_resizer.h
index 8bf0657..a05039b 100644
--- a/ash/wm/workspace/workspace_window_resizer.h
+++ b/ash/wm/workspace/workspace_window_resizer.h
@@ -61,13 +61,18 @@ class ASH_EXPORT WorkspaceWindowResizer : public WindowResizer {
   void RevertDrag() override;
 
  private:
+  WorkspaceWindowResizer(wm::WindowState* window_state,
+                         const std::vector<aura::Window*>& attached_windows);
+
+ private:
   friend class WorkspaceWindowResizerTest;
 
   // The edge to which the window should be snapped at the end of the drag.
-  enum SnapType { SNAP_LEFT, SNAP_RIGHT, SNAP_NONE };
-
-  WorkspaceWindowResizer(wm::WindowState* window_state,
-                         const std::vector<aura::Window*>& attached_windows);
+  enum SnapType {
+    SNAP_LEFT,
+    SNAP_RIGHT,
+    SNAP_NONE
+  };
 
   // Lays out the attached windows. |bounds| is the bounds of the main window.
   void LayoutAttachedWindows(gfx::Rect* bounds);