Add pin icon to the omnibar in windows 8 metro mode.

chrome/browser/ui/metro_pin_tab_helper.cc

Index: chrome/browser/ui/metro_pin_tab_helper.cc
diff --git a/chrome/browser/ui/metro_pin_tab_helper.cc b/chrome/browser/ui/metro_pin_tab_helper.cc
index 0a16543cdfdffc42f1b389fe0db7a5a0e9988daf..a525c20905ebb65d4c6f05bd621a54ed5069b930 100644
--- a/chrome/browser/ui/metro_pin_tab_helper.cc
+++ b/chrome/browser/ui/metro_pin_tab_helper.cc
@@ -12,9 +12,12 @@
 #include "base/win/metro.h"
 #endif
 
+MetroPinTabHelper::Delegate::~Delegate() {}
+
 MetroPinTabHelper::MetroPinTabHelper(content::WebContents* web_contents)
     : content::WebContentsObserver(web_contents),
-      is_pinned_(false) {}
+      is_pinned_(false),
+      delegate_(NULL) {}
 
 MetroPinTabHelper::~MetroPinTabHelper() {}
 
@@ -40,8 +43,7 @@ void MetroPinTabHelper::TogglePinnedToStartScreen() {
     // TODO(benwells): This will update the state incorrectly if the user
     // cancels. To fix this some sort of callback needs to be introduced as
     // the pinning happens on another thread.
-    is_pinned_ = !is_pinned_;
-    return;
+    SetIsPinned(!is_pinned_);
   }
 #endif
 }
@@ -66,9 +68,16 @@ void MetroPinTabHelper::UpdatePinnedStateForCurrentURL() {
     }
 
     GURL url = web_contents()->GetURL();
-    is_pinned_ = metro_is_pinned_to_start_screen(UTF8ToUTF16(url.spec())) != 0;
+    SetIsPinned(metro_is_pinned_to_start_screen(UTF8ToUTF16(url.spec())) != 0);
     VLOG(1) << __FUNCTION__ << " with url " << UTF8ToUTF16(url.spec())
             << " result: " << is_pinned_;
   }
 #endif
 }
+
+void MetroPinTabHelper::SetIsPinned(bool is_pinned) {
+  bool was_pinned = is_pinned_;
+  is_pinned_ = is_pinned;
+  if (delegate_ && is_pinned_ != was_pinned)
+    delegate_->IsPinnedChanged(web_contents(), is_pinned_);
+}