Move auto-hiding desktop bar computation from PanelManager to DisplaySettingsProvider

BUG=none
TEST=existing tests due to no new functionality

Review URL: https://chromiumcodereview.appspot.com/9689035

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@131570 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 49 insertions, 13 deletions

diff --git a/chrome/browser/ui/panels/display_settings_provider.cc b/chrome/browser/ui/panels/display_settings_provider.cc
index a6652a1..af3ee88 100644
--- a/chrome/browser/ui/panels/display_settings_provider.cc
+++ b/chrome/browser/ui/panels/display_settings_provider.cc
@@ -7,15 +7,23 @@
 #include "base/logging.h"
 #include "ui/gfx/screen.h"
 
-DisplaySettingsProvider::DisplaySettingsProvider(Observer* observer)
-    : observer_(observer) {
-  DCHECK(observer);
+DisplaySettingsProvider::DisplaySettingsProvider()
+    : display_area_observer_(NULL),
+      desktop_bar_observer_(NULL) {
 }
 
 DisplaySettingsProvider::~DisplaySettingsProvider() {
 }
 
-gfx::Rect DisplaySettingsProvider::GetWorkArea() {
+gfx::Rect DisplaySettingsProvider::GetDisplayArea() {
+  // Do the first-time initialization if not yet.
+  if (adjusted_work_area_.IsEmpty())
+    OnDisplaySettingsChanged();
+
+  return adjusted_work_area_;
+}
+
+gfx::Rect DisplaySettingsProvider::GetWorkArea() const {
 #if defined(OS_MACOSX)
   // On OSX, panels should be dropped all the way to the bottom edge of the
   // screen (and overlap Dock).
@@ -23,16 +31,24 @@ gfx::Rect DisplaySettingsProvider::GetWorkArea() {
 #else
   gfx::Rect work_area = gfx::Screen::GetPrimaryMonitorWorkArea();
 #endif
+  return work_area;
+}
 
-  if (work_area_ != work_area) {
-    work_area_ = work_area;
-    OnWorkAreaChanged();
-  }
+void DisplaySettingsProvider::OnDisplaySettingsChanged() {
+  gfx::Rect work_area = GetWorkArea();
+  if (work_area == work_area_)
+    return;
+  work_area_ = work_area;
 
-  return work_area;
+  OnAutoHidingDesktopBarChanged();
 }
 
-void DisplaySettingsProvider::OnWorkAreaChanged() {
+void DisplaySettingsProvider::OnAutoHidingDesktopBarChanged() {
+  gfx::Rect old_adjusted_work_area = adjusted_work_area_;
+  AdjustWorkAreaForAutoHidingDesktopBars();
+
+  if (old_adjusted_work_area != adjusted_work_area_ && display_area_observer_)
+    display_area_observer_->OnDisplayAreaChanged(adjusted_work_area_);
 }
 
 bool DisplaySettingsProvider::IsAutoHidingDesktopBarEnabled(
@@ -51,9 +67,29 @@ DisplaySettingsProvider::GetDesktopBarVisibility(
   return DESKTOP_BAR_VISIBLE;
 }
 
-#if !defined(OS_WIN) || defined(USE_AURA)
+void DisplaySettingsProvider::AdjustWorkAreaForAutoHidingDesktopBars() {
+  // Note that we do not care about the top desktop bar since panels could not
+  // reach so high due to size constraint. We also do not care about the bottom
+  // desktop bar since we always align the panel to the bottom of the work area.
+  adjusted_work_area_ = work_area_;
+  if (IsAutoHidingDesktopBarEnabled(
+      DisplaySettingsProvider::DESKTOP_BAR_ALIGNED_LEFT)) {
+    int space = GetDesktopBarThickness(
+        DisplaySettingsProvider::DESKTOP_BAR_ALIGNED_LEFT);
+    adjusted_work_area_.set_x(adjusted_work_area_.x() + space);
+    adjusted_work_area_.set_width(adjusted_work_area_.width() - space);
+  }
+  if (IsAutoHidingDesktopBarEnabled(
+      DisplaySettingsProvider::DESKTOP_BAR_ALIGNED_RIGHT)) {
+    int space = GetDesktopBarThickness(
+        DisplaySettingsProvider::DESKTOP_BAR_ALIGNED_RIGHT);
+    adjusted_work_area_.set_width(adjusted_work_area_.width() - space);
+  }
+}
+
+#if defined(USE_AURA)
 // static
-DisplaySettingsProvider* DisplaySettingsProvider::Create(Observer* observer) {
-  return new DisplaySettingsProvider(observer);
+DisplaySettingsProvider* DisplaySettingsProvider::Create() {
+  return new DisplaySettingsProvider();
 }
 #endif