MacViews: Fix sending mouse exit event and releasing capture on D&D.

ui/base/cocoa/base_view.mm

Index: ui/base/cocoa/base_view.mm
diff --git a/ui/base/cocoa/base_view.mm b/ui/base/cocoa/base_view.mm
index 47ccca96ad6dd866b986183dbbec4db376f85be6..1fbd5adf517bac3dc3bee68cda18d782ac32a3d1 100644
--- a/ui/base/cocoa/base_view.mm
+++ b/ui/base/cocoa/base_view.mm
@@ -83,7 +83,6 @@ NSString* kSelectionDirection = @"Chromium.kSelectionDirection";
 }
 
 - (void)mouseDown:(NSEvent*)theEvent {
-  dragging_ = YES;
   [self mouseEvent:theEvent];
 }
 
@@ -97,22 +96,6 @@ NSString* kSelectionDirection = @"Chromium.kSelectionDirection";
 
 - (void)mouseUp:(NSEvent*)theEvent {
   [self mouseEvent:theEvent];
-
-  dragging_ = NO;
-  if (pendingExitEvent_.get()) {
-    NSEvent* exitEvent =
-        [NSEvent enterExitEventWithType:NSMouseExited
-                               location:[theEvent locationInWindow]
-                          modifierFlags:[theEvent modifierFlags]
-                              timestamp:[theEvent timestamp]
-                           windowNumber:[theEvent windowNumber]
-                                context:[theEvent context]
-                            eventNumber:[pendingExitEvent_.get() eventNumber]
-                         trackingNumber:[pendingExitEvent_.get() trackingNumber]
-                               userData:[pendingExitEvent_.get() userData]];
-    [self mouseEvent:exitEvent];
-    pendingExitEvent_.reset();
-  }
 }
 
 - (void)rightMouseUp:(NSEvent*)theEvent {
@@ -140,23 +123,10 @@ NSString* kSelectionDirection = @"Chromium.kSelectionDirection";
 }
 
 - (void)mouseEntered:(NSEvent*)theEvent {
-  if (pendingExitEvent_.get()) {
-    pendingExitEvent_.reset();
-    return;
-  }
-
   [self mouseEvent:theEvent];
 }
 
 - (void)mouseExited:(NSEvent*)theEvent {
-  // The tracking area will send an exit event even during a drag, which isn't
-  // how the event flow for drags should work. This stores the exit event, and
-  // sends it when the drag completes instead.
-  if (dragging_) {
-    pendingExitEvent_.reset([theEvent retain]);
-    return;
-  }
-
   [self mouseEvent:theEvent];
 }