Fix partial-screen flashes when first entering low power full screen.

NSWindow resizing is slow, so try to guess the right size when first creating
the window. Furthermore, resizing the window will create implicit animations for
the Window's views and layers. Disable those implicit animations.

BUG=667511

Review-Url: https://codereview.chromium.org/2539863002
Cr-Commit-Position: refs/heads/master@{#435062}

chrome/browser/ui/cocoa/fullscreen_low_power_coordinator.mm

@@ -25,8 +25,13 @@ const uint64_t kWarmUpFramesBeforeEnteringLowPowerMode = 30;
 @implementation FullscreenLowPowerWindow
 - (id)initWithEventTargetWindow:(NSWindow*)eventTargetWindow
                       withLayer:(CALayer*)layer {
+  // Resizing an NSWindow can be slow, so try to guess the right size at
+  // creation.
+  NSRect screenFrame = [[eventTargetWindow screen] frame];
+  NSRect initialRect = NSMakeRect(
+      0, 0, NSWidth(screenFrame), NSHeight(screenFrame));
   if (self = [super
-          initWithContentRect:NSMakeRect(0, 0, 256, 256)
+          initWithContentRect:initialRect
                     styleMask:NSTitledWindowMask | NSResizableWindowMask |
                               NSFullSizeContentViewWindowMask
                       backing:NSBackingStoreBuffered
@@ -186,6 +191,10 @@ void FullscreenLowPowerCoordinatorCocoa::EnterOrExitLowPowerModeIfNeeded() {
         // Ensure that the window's frame and style are set, and order it behind
         // the main window, so that it's ready to be moved in front.
         state_ = WarmingUp;
+
+        // Changing the size of the Window will also change the size of the
+        // views/layers. Disable implicit animations.
+        ScopedCAActionDisabler disabler;
         [low_power_window_ setStyleMask:[low_power_window_ styleMask] |
                                         NSFullScreenWindowMask];
         [low_power_window_ setFrame:[content_window_ frame]