Fix bing images crash

 Bug: 4517571
 Caused by receiving onPageFinished callbacks for in page navigation links
 (eg, url#something).
 Also, only post an UPDATE_BOOKMARK_THUMBNAIL message if one is not already
 pending for the tab.

Change-Id: Ia45ae93206507b93ad6fc841ad291b97bc947675
diff --git a/src/com/android/browser/Tab.java b/src/com/android/browser/Tab.java
index d8a3af9..62b574d 100644
--- a/src/com/android/browser/Tab.java
+++ b/src/com/android/browser/Tab.java
@@ -555,6 +555,11 @@
 
         @Override
         public void onPageFinished(WebView view, String url) {
+            if (!mInPageLoad) {
+                // In page navigation links (www.something.com#footer) will
+                // trigger an onPageFinished which we don't care about.
+                return;
+            }
             if (!isPrivateBrowsingEnabled()) {
                 LogTag.logPageFinishedLoading(
                         url, SystemClock.uptimeMillis() - mLoadStartTime);