Revert 31814 - Testing to see if it caused performance problems....

chrome/browser/cocoa/tab_strip_controller.mm

 // Copyright (c) 2009 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #import "chrome/browser/cocoa/tab_strip_controller.h"
 
 #import <QuartzCore/QuartzCore.h>
 
 #include <limits>
 
@@ skipping 89 matching lines @@
 - (void)addSubviewToPermanentList:(NSView*)aView;
 - (void)regenerateSubviewList;
 - (NSInteger)indexForContentsView:(NSView*)view;
 - (void)updateFavIconForContents:(TabContents*)contents
                          atIndex:(NSInteger)index;
 - (void)layoutTabsWithAnimation:(BOOL)animate
              regenerateSubviews:(BOOL)doUpdate;
 - (void)animationDidStopForController:(TabController*)controller
                              finished:(BOOL)finished;
 - (NSInteger)indexFromModelIndex:(NSInteger)index;
-- (void)mouseMoved:(NSEvent*)event;
 @end
 
 // A simple view class that prevents the Window Server from dragging the area
 // behind tabs. Sometimes core animation confuses it. Unfortunately, it can also
 // falsely pick up clicks during rapid tab closure, so we have to account for
 // that.
 @interface TabStripControllerDragBlockingView : NSView {
   TabStripController* controller_;  // weak; owns us
 }
 
@@ skipping 765 matching lines @@
 // controller and remove the view from the strip.
 - (void)removeTab:(TabController*)controller {
   NSUInteger index = [tabArray_ indexOfObject:controller];
 
   // Release the tab contents controller so those views get destroyed. This
   // will remove all the tab content Cocoa views from the hierarchy. A
   // subsequent "select tab" notification will follow from the model. To
   // tell us what to swap in in its absence.
   [tabContentsArray_ removeObjectAtIndex:index];
 
+  // Remove the view from the tab strip.
   NSView* tab = [controller view];
-
-  // Stop observing the tab's tracking areas.
-  NSNotificationCenter* defaultCenter = [NSNotificationCenter defaultCenter];
-  [defaultCenter removeObserver:self
-                           name:NSViewDidUpdateTrackingAreasNotification
-                         object:tab];
-
-  // Remove the view from the tab strip.
   [tab removeFromSuperview];
 
   // Clear the tab controller's target.
   // TODO(viettrungluu): [crbug.com/23829] Find a better way to handle the tab
   // controller's target.
   [controller setTarget:nil];
 
   if ([hoveredTab_ isEqual:tab])
     hoveredTab_ = nil;
 
@@ skipping 269 matching lines @@
 
 // Called when the tab strip view changes size. As we only registered for
 // changes on our view, we know it's only for our view. Layout w/out
 // animations since they are blocked by the resize nested runloop. We need
 // the views to adjust immediately. Neither the tabs nor their z-order are
 // changed, so we don't need to update the subviews.
 - (void)tabViewFrameChanged:(NSNotification*)info {
   [self layoutTabsWithAnimation:NO regenerateSubviews:NO];
 }
 
-// Called when the tracking areas for any given tab are updated. This allows
-// the individual tabs to update their hover states correctly.
-// Only generates the event if the cursor is in the tab strip.
-- (void)tabUpdateTracking:(NSNotification*)notification {
-  DCHECK([[notification object] isKindOfClass:[TabView class]]);
-  NSWindow* window = [tabView_ window];
-  NSPoint location = [window mouseLocationOutsideOfEventStream];
-  if (NSPointInRect(location, [tabView_ frame])) {
-    NSEvent* mouseEvent = [NSEvent mouseEventWithType:NSMouseMoved
-                                             location:location
-                                        modifierFlags:0
-                                            timestamp:0
-                                         windowNumber:[window windowNumber]
-                                              context:nil
-                                          eventNumber:0
-                                           clickCount:0
-                                             pressure:0];
-    [self mouseMoved:mouseEvent];
-  }
-}
-
 - (BOOL)inRapidClosureMode {
   return availableResizeWidth_ != kUseFullAvailableWidth;
 }
 
 // Disable tab dragging when there are any pending animations.
 - (BOOL)tabDraggingAllowed {
   return [closingControllers_ count] == 0;
 }
 
 - (void)mouseMoved:(NSEvent*)event {
@@ skipping 49 matching lines @@
   [permanentSubviews_ addObject:aView];
 }
 
 // Update the subviews, keeping the permanent ones (or, more correctly, putting
 // in the ones listed in permanentSubviews_), and putting in the current tabs in
 // the correct z-order. Any current subviews which is neither in the permanent
 // list nor a (current) tab will be removed. So if you add such a subview, you
 // should call |-addSubviewToPermanentList:| (or better yet, call that and then
 // |-regenerateSubviewList| to actually add it).
 - (void)regenerateSubviewList {
-  // Remove self as an observer from all the old tabs before a new set of
-  // potentially different tabs is put in place.
-  NSNotificationCenter* defaultCenter = [NSNotificationCenter defaultCenter];
-  for (NSView* view in [tabView_ subviews]) {
-    [defaultCenter removeObserver:self
-                             name:NSViewDidUpdateTrackingAreasNotification
-                           object:view];
-  }
-
   // Subviews to put in (in bottom-to-top order), beginning with the permanent
   // ones.
   NSMutableArray* subviews = [NSMutableArray arrayWithArray:permanentSubviews_];
 
   NSView* selectedTabView = nil;
   // Go through tabs in reverse order, since |subviews| is bottom-to-top.
   for (TabController* tab in [tabArray_.get() reverseObjectEnumerator]) {
-    NSView* tabView = [tab view];
-
-    // Set self up to observe tabs so hover states will be correct as tabs move.
-    [defaultCenter addObserver:self
-                      selector:@selector(tabUpdateTracking:)
-                          name:NSViewDidUpdateTrackingAreasNotification
-                        object:tabView];
-
     if ([tab selected]) {
       DCHECK(!selectedTabView);
-      selectedTabView = tabView;
+      selectedTabView = [tab view];
     } else {
-      [subviews addObject:tabView];
+      [subviews addObject:[tab view]];
     }
   }
   if (selectedTabView)
     [subviews addObject:selectedTabView];
 
   [tabView_ setSubviews:subviews];
 }
 
 - (GTMWindowSheetController*)sheetController {
   if (!sheetController_.get())
@@ skipping 55 matching lines @@
   NSInteger index = [self indexFromModelIndex:modelIndex];
   BrowserWindowController* controller =
       (BrowserWindowController*)[[switchView_ window] windowController];
   DCHECK(index >= 0);
   if (index >= 0) {
     [controller setTab:[self viewAtIndex:index] isDraggable:YES];
   }
 }
 
 @end