Refactor browser window zoom handling and enable zoom icon on all platforms.

chrome/browser/ui/cocoa/browser_window_cocoa.mm

Index: chrome/browser/ui/cocoa/browser_window_cocoa.mm
diff --git a/chrome/browser/ui/cocoa/browser_window_cocoa.mm b/chrome/browser/ui/cocoa/browser_window_cocoa.mm
index 1592370facceb4f2cf2a6cc120fbca2f0bd252b3..1cf9fbf9e9a0b7f49a8a9ce60d822640c0e26cee 100644
--- a/chrome/browser/ui/cocoa/browser_window_cocoa.mm
+++ b/chrome/browser/ui/cocoa/browser_window_cocoa.mm
@@ -248,16 +248,8 @@ void BrowserWindowCocoa::SetStarredState(bool is_starred) {
   [controller_ setStarredState:is_starred ? YES : NO];
 }
 
-void BrowserWindowCocoa::SetZoomIconState(ZoomController::ZoomIconState state) {
-  // TODO(khorimoto): Find someone to implement this.
-}
-
-void BrowserWindowCocoa::SetZoomIconTooltipPercent(int zoom_percent) {
-  // TODO(khorimoto): Find someone to implement this.
-}
-
-void BrowserWindowCocoa::ShowZoomBubble(int zoom_percent) {
-  // TODO(khorimoto): Find someone to implement this.
+void BrowserWindowCocoa::ZoomChangedForActiveTab(bool can_show_bubble) {
+  [controller_ locationBarBridge]->ZoomChangedForActiveTab(can_show_bubble);
 }
 
 gfx::Rect BrowserWindowCocoa::GetRestoredBounds() const {