Always broadcast one last "tab not blocked" notification before closing a tab.

chrome/browser/ui/tabs/tab_strip_model.cc

Index: chrome/browser/ui/tabs/tab_strip_model.cc
diff --git a/chrome/browser/ui/tabs/tab_strip_model.cc b/chrome/browser/ui/tabs/tab_strip_model.cc
index dfad932240f11a5d7e939b29bdf33403f933d6e0..17b6d2ed91287d1ef02b3770e96eb7c821035884 100644
--- a/chrome/browser/ui/tabs/tab_strip_model.cc
+++ b/chrome/browser/ui/tabs/tab_strip_model.cc
@@ -1250,6 +1250,12 @@ bool TabStripModel::InternalCloseTabs(const std::vector<int>& indices,
 void TabStripModel::InternalCloseTab(WebContents* contents,
                                      int index,
                                      bool create_historical_tabs) {
+  // Reset the blocked state of the tab, and fire a notification if necessary.
+  // <http://crbug.com/336386#c4> . TODO(avi): Remove all the "blocked" code and
+  // the WebContentsModalDialogManager from TabStripModel, and move all that
+  // tracking code to the modal dialog code, where it belongs.
+  SetTabBlocked(index, false);
+
   FOR_EACH_OBSERVER(TabStripModelObserver, observers_,
                     TabClosingAt(this, contents, index));