Fix for "Mouseovers follow the cursor even when there's a find bar in the way"

chrome/browser/renderer_host/render_widget_host_view_mac.mm

 // Copyright (c) 2011 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.
 
 #include <QuartzCore/QuartzCore.h>
 
 #include "chrome/browser/renderer_host/render_widget_host_view_mac.h"
 
 #include "app/surface/io_surface_support_mac.h"
 #include "base/command_line.h"
@@ skipping 1399 matching lines @@
 @synthesize caretRect = caretRect_;
 
 - (id)initWithRenderWidgetHostViewMac:(RenderWidgetHostViewMac*)r {
   self = [super initWithFrame:NSZeroRect];
   if (self) {
     editCommand_helper_.reset(new RWHVMEditCommandHelper);
     editCommand_helper_->AddEditingSelectorsToClass([self class]);
 
     renderWidgetHostView_.reset(r);
     canBeKeyView_ = YES;
-    takesFocusOnlyOnMouseDown_ = NO;
-    closeOnDeactivate_ = NO;
     focusedPluginIdentifier_ = -1;
   }
   return self;
 }
 
 - (void)setCanBeKeyView:(BOOL)can {
   canBeKeyView_ = can;
 }
 
 - (void)setTakesFocusOnlyOnMouseDown:(BOOL)b {
   takesFocusOnlyOnMouseDown_ = b;
 }
 
 - (void)setCloseOnDeactivate:(BOOL)b {
   closeOnDeactivate_ = b;
 }
 
 - (void)mouseEvent:(NSEvent*)theEvent {
+  // Use hitTest to check whether the mouse is over a nonWebContentView - in
+  // which case the mouse event should not be handled by the render host.
+  const SEL nonWebContentViewSelector = @selector(nonWebContentView);
+  NSView* contentView = [[self window] contentView];
+  NSView* view = [contentView hitTest:[theEvent locationInWindow]];
+  // Traverse the superview hierarchy as the hitTest will return the frontmost
+  // view, such as an NSTextView, while nonWebContentView may be specified by
+  // its parent view.
+  while (view) {
+    if ([view respondsToSelector:nonWebContentViewSelector] &&
+        [view performSelector:nonWebContentViewSelector]) {
+      // The cursor is over a nonWebContentView - ignore this mouse event.
+      // If this is the first such event, send a mouse exit to the host view.
+      if (!mouseEventWasIgnored_ &&
+          renderWidgetHostView_->render_widget_host_) {
+        WebMouseEvent exitEvent =
+            WebInputEventFactory::mouseEvent(theEvent, self);
+        exitEvent.type = WebInputEvent::MouseLeave;
+        exitEvent.button = WebMouseEvent::ButtonNone;
+        renderWidgetHostView_->render_widget_host_->ForwardMouseEvent(
+            exitEvent);
+      }
+      mouseEventWasIgnored_ = YES;
+      return;
+    }
+    view = [view superview];
+  }
+
+  if (mouseEventWasIgnored_) {
+    // If this is the first mouse event after a previous event that was ignored
+    // due to the hitTest, send a mouse enter event to the host view.
+    if (renderWidgetHostView_->render_widget_host_) {
+      WebMouseEvent enterEvent =
+          WebInputEventFactory::mouseEvent(theEvent, self);
+      enterEvent.type = WebInputEvent::MouseMove;
+      enterEvent.button = WebMouseEvent::ButtonNone;
+      renderWidgetHostView_->render_widget_host_->ForwardMouseEvent(enterEvent);
+    }
+  }
+  mouseEventWasIgnored_ = NO;
+
   // TODO(rohitrao): Probably need to handle other mouse down events here.
   if ([theEvent type] == NSLeftMouseDown && takesFocusOnlyOnMouseDown_) {
     if (renderWidgetHostView_->render_widget_host_)
       renderWidgetHostView_->render_widget_host_->OnMouseActivate();
 
     // Manually take focus after the click but before forwarding it to the
     // renderer.
     [[self window] makeFirstResponder:self];
   }
 
@@ skipping 1413 matching lines @@
   if (!string) return NO;
 
   // If the user is currently using an IME, confirm the IME input,
   // and then insert the text from the service, the same as TextEdit and Safari.
   [self confirmComposition];
   [self insertText:string];
   return YES;
 }
 
 @end