Don't capture picture

  Bug: 6439427

Change-Id: I7704d8c81bbb9e612faf3a3206cee245e746035b
diff --git a/src/com/android/browser/Tab.java b/src/com/android/browser/Tab.java
index 712e30a..28734bd 100644
--- a/src/com/android/browser/Tab.java
+++ b/src/com/android/browser/Tab.java
@@ -185,6 +185,7 @@
     private int mCaptureHeight;
     private Bitmap mCapture;
     private Handler mHandler;
+    private boolean mUpdateThumbnail;
 
     /**
      * See {@link #clearBackStackWhenItemAdded(String)}.
@@ -334,6 +335,7 @@
         @Override
         public void onPageStarted(WebView view, String url, Bitmap favicon) {
             mInPageLoad = true;
+            mUpdateThumbnail = true;
             mPageLoadProgress = INITIAL_PROGRESS;
             mCurrentState = new PageState(mContext,
                     view.isPrivateBrowsingEnabled(), url, favicon);
@@ -792,6 +794,9 @@
                 mInPageLoad = false;
             }
             mWebViewController.onProgressChanged(Tab.this);
+            if (mUpdateThumbnail && newProgress == 100) {
+                mUpdateThumbnail = false;
+            }
         }
 
         @Override
@@ -1203,6 +1208,10 @@
         };
     }
 
+    public boolean shouldUpdateThumbnail() {
+        return mUpdateThumbnail;
+    }
+
     /**
      * This is used to get a new ID when the tab has been preloaded, before it is displayed and
      * added to TabControl. Preloaded tabs can be created before restoreInstanceState, leading
@@ -1925,7 +1934,6 @@
 
     @Override
     public void onNewPicture(WebView view, Picture picture) {
-        //update screenshot
         postCapture();
     }