Fixes couple of bugs in the TabStrip that could cause tabs to dance

around. Both only occurred when the active tab width differs from
inactive tab width (lots-o-tabs).
. ResizeLayoutTabs() had an optimization that avoided doing anything
  if the width of the first tab hasn't changed. Problems is if the
  first tab is active and inactive tabs have a smaller width than
  active tabs than the width won't have changed but we still need to
  layout. I removed the optimization.
. If selecting a tab triggers a bounds change the coordinates used by
  tab dragging would be wrong (because they extract them from the
  event, which is in the original coordinates).
. Needed to tweak rtl code.

BUG=140747
TEST=see bug, but make sure no weird behavior with tab selection/dragging on
windows/chrome-os.
R=ben@chromium.org


Review URL: https://chromiumcodereview.appspot.com/11821036

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@175991 0039d316-1c4b-4281-b951-d872f2087c98

chrome/browser/ui/views/tabs/tab.cc

@@ -867,6 +867,11 @@ bool Tab::OnMousePressed(const ui::MouseEvent& event) {
       (event.IsOnlyRightMouseButton() && event.flags() & ui::EF_FROM_TOUCH)) {
     ui::ListSelectionModel original_selection;
     original_selection.Copy(controller()->GetSelectionModel());
+    // Changing the selection may cause our bounds to change. If that happens
+    // the location of the event may no longer be valid. Create a copy of the
+    // event in the parents coordinate, which won't change, and recreate an
+    // event after changing so the coordinates are correct.
+    ui::MouseEvent event_in_parent(event, static_cast<View*>(this), parent());
     if (controller()->SupportsMultipleSelection()) {
       if (event.IsShiftDown() && event.IsControlDown()) {
         controller()->AddSelectionFromAnchorTo(this);
@@ -884,7 +889,9 @@ bool Tab::OnMousePressed(const ui::MouseEvent& event) {
     } else if (!IsSelected()) {
       controller()->SelectTab(this);
     }
-    controller()->MaybeStartDrag(this, event, original_selection);
+    ui::MouseEvent cloned_event(event_in_parent, parent(),
+                                static_cast<View*>(this));
+    controller()->MaybeStartDrag(this, cloned_event, original_selection);
   }
   return true;
 }
@@ -963,13 +970,18 @@ void Tab::OnGestureEvent(ui::GestureEvent* event) {
       if (event->details().touch_points() != 1)
         return;
 
+      // See comment in OnMousePressed() as to why we copy the event.
+      ui::GestureEvent event_in_parent(*event, static_cast<View*>(this),
+                                       parent());
       ui::ListSelectionModel original_selection;
       original_selection.Copy(controller()->GetSelectionModel());
       if (!IsSelected())
         controller()->SelectTab(this);
       gfx::Point loc(event->location());
       views::View::ConvertPointToScreen(this, &loc);
-      controller()->MaybeStartDrag(this, *event, original_selection);
+      ui::GestureEvent cloned_event(event_in_parent, parent(),
+                                    static_cast<View*>(this));
+      controller()->MaybeStartDrag(this, cloned_event, original_selection);
       break;
     }
 

chrome/browser/ui/views/tabs/tab_drag_controller.cc

@@ -364,7 +364,6 @@ TabDragController::TabDragController()
       attached_tabstrip_(NULL),
       screen_(NULL),
       host_desktop_type_(chrome::HOST_DESKTOP_TYPE_NATIVE),
-      source_tab_offset_(0),
       offset_to_width_ratio_(0),
       old_focused_view_(NULL),
       last_move_screen_loc_(0),
@@ -431,7 +430,6 @@ void TabDragController::Init(
       source_tabstrip->GetWidget()->GetNativeView());
   host_desktop_type_ = chrome::GetHostDesktopTypeForNativeView(
       source_tabstrip->GetWidget()->GetNativeView());
-  source_tab_offset_ = source_tab_offset;
   start_point_in_screen_ = gfx::Point(source_tab_offset, mouse_offset.y());
   views::View::ConvertPointToScreen(source_tab, &start_point_in_screen_);
   mouse_offset_ = mouse_offset;
@@ -453,7 +451,8 @@ void TabDragController::Init(
   MessageLoopForUI::current()->AddObserver(this);
 
   if (source_tab->width() > 0) {
-    offset_to_width_ratio_ = static_cast<float>(source_tab_offset_) /
+    offset_to_width_ratio_ = static_cast<float>(
+        source_tab->GetMirroredXInView(source_tab_offset)) /
         static_cast<float>(source_tab->width());
   }
   InitWindowCreatePoint();

chrome/browser/ui/views/tabs/tab_drag_controller.h

@@ -499,10 +499,7 @@ class TabDragController : public content::WebContentsDelegate,
   // detached window is created at the right location.
   gfx::Point mouse_offset_;
 
-  // Offset of the mouse relative to the source tab.
-  int source_tab_offset_;
-
-  // Ratio of the x-coordinate of the |source_tab_offset_| to the width of the
+  // Ratio of the x-coordinate of the |source_tab_offset| to the width of the
   // tab. Not used for vertical tabs.
   float offset_to_width_ratio_;
 

chrome/browser/ui/views/tabs/tab_strip.cc

@@ -1089,7 +1089,7 @@ void TabStrip::MaybeStartDrag(
     GetWidget()->SetCapture(this);
   drag_controller_.reset(new TabDragController);
   drag_controller_->Init(
-      this, tab, tabs, gfx::Point(x, y), tab->GetMirroredXInView(event.x()),
+      this, tab, tabs, gfx::Point(x, y), event.x(),
       selection_model, detach_behavior, move_behavior);
 }
 
@@ -2125,16 +2125,11 @@ void TabStrip::ResizeLayoutTabs() {
     // mini-tabs have the same width), so there is nothing to do.
     return;
   }
-  Tab* first_tab  = tab_at(mini_tab_count);
-  double unselected, selected;
-  GetDesiredTabWidths(tab_count(), mini_tab_count, &unselected, &selected);
-  // TODO: this is always selected, should it be 'selected : unselected'?
-  int w = Round(first_tab->IsActive() ? selected : selected);
-
-  // We only want to run the animation if we're not already at the desired
-  // size.
-  if (abs(first_tab->width() - w) > 1)
-    StartResizeLayoutAnimation();
+  // Don't try and avoid layout based on tab sizes. If tabs are small enough
+  // then the width of the active tab may not change, but other widths may
+  // have. This is particularly important if we've overflowed (all tabs are at
+  // the min).
+  StartResizeLayoutAnimation();
 }
 
 void TabStrip::ResizeLayoutTabsFromTouch() {