Reland ash: Use immersive mode for fullscreen

* Remove immersive mode button from maximized window frame
* Tie immersive mode to browser-fullscreen only, keep tab-fullscreen
with existing UI
* Size button exits immersive mode
* Add ImageButton::GetImage for testing
* Most browser commands are enabled in immersive fullscreen

BUG=177549
TEST=added to browser_tests views_unittests ash_unittests

Original review: https://codereview.chromium.org/12316086/

Review URL: https://chromiumcodereview.appspot.com/12328119

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@184908 0039d316-1c4b-4281-b951-d872f2087c98
diff --git a/chrome/browser/ui/cocoa/browser_window_cocoa.mm b/chrome/browser/ui/cocoa/browser_window_cocoa.mm
index fe0670f4..ba96f4c 100644
--- a/chrome/browser/ui/cocoa/browser_window_cocoa.mm
+++ b/chrome/browser/ui/cocoa/browser_window_cocoa.mm
@@ -355,6 +355,11 @@
   [controller_ updateFullscreenExitBubbleURL:url bubbleType:bubble_type];
 }
 
+bool BrowserWindowCocoa::ShouldHideUIForFullscreen() const {
+  // On Mac, fullscreen mode has most normal things (in a slide-down panel).
+  return false;
+}
+
 bool BrowserWindowCocoa::IsFullscreen() const {
   if ([controller_ inPresentationMode])
     CHECK([controller_ isFullscreen]);  // Presentation mode must be fullscreen.