[Mac] Make app window backgrounds white.

chrome/browser/ui/cocoa/apps/native_app_window_cocoa.mm

Index: chrome/browser/ui/cocoa/apps/native_app_window_cocoa.mm
diff --git a/chrome/browser/ui/cocoa/apps/native_app_window_cocoa.mm b/chrome/browser/ui/cocoa/apps/native_app_window_cocoa.mm
index a4ad4eabc04d88a0f14caf214ffa876118597cd7..23c9868eed196217fa10cc7af24fd2b26f8fdbef 100644
--- a/chrome/browser/ui/cocoa/apps/native_app_window_cocoa.mm
+++ b/chrome/browser/ui/cocoa/apps/native_app_window_cocoa.mm
@@ -217,6 +217,27 @@ std::vector<gfx::Rect> CalculateNonDraggableRegions(
   return YES;
 }
 
+- (void)drawCustomFrameRect:(NSRect)rect forView:(NSView*)view {
+  // Make the background color of the content area white. We can't just call
+  // -setBackgroundColor as that causes the title bar to be drawn in a solid
+  // color.
+  NSRect contentRect = [NSWindow contentRectForFrameRect:rect

[tapted, 2014/06/17 06:09:51]

I think you can use [self contentRectForFrameRect:rect];

[jackhou1, 2014/06/17 07:00:14]

Done.

+                                               styleMask:[self styleMask]];
+  [[NSColor whiteColor] set];
+  NSRectFill(contentRect);
+
+  // Draw the native title bar. We clip the content area since the native
+  // implementation draws a grey background.

[tapted, 2014/06/17 06:09:52]

nit: grey -> gray to be consistent with color :p

[jackhou1, 2014/06/17 07:00:14]

Done.

+  NSRect titleBarRect = NSIntersectionRect(rect,
+                                           NSMakeRect(NSMinX(contentRect),

[tapted, 2014/06/17 06:09:51]

I stared at the second argument for a while before realising what it was doing
(I was reading NSMaxY as NSMinY). Pity there's no NSSubtractRect (I think).

Maybe rename:
 rect -> frameRect
 contentRect -> rect

Then do

rect.origin.y = NSMaxY(rect);
rect.size.height = CGFLOAT_MAX;
rect = NSIntersectionRect(rect, frameRect);


I think this makes it clearer what's changing.

[jackhou1, 2014/06/17 07:00:14]

Done.

+                                                      NSMaxY(contentRect),
+                                                      NSWidth(contentRect),
+                                                      CGFLOAT_MAX));
+  [NSBezierPath clipRect:titleBarRect];

[tapted, 2014/06/17 06:09:52]

It's possible clipping will be more expensive than just painting the full area
twice (assuming that actually works) (but I'm guessing, so probably not worth
worrying about)

+  [super drawCustomFrameRect:rect
+                     forView:view];
+}
+
 @end
 
 @interface ShellCustomFrameNSWindow : ShellNSWindow {