Merge revision 448 and 453 changes:

- Add support for running unit tests without multi-threaded message loop mode (issue #338).
- Mac: Fix unit test expectations.
- Mac: cef_time_t.day_of_week is not supported.
- Mac: Add support for building the 'Run cef_unittests' target from the command line.


git-svn-id: https://chromiumembedded.googlecode.com/svn/branches/963@455 5089003a-bbd8-11dd-ad1f-f1f9622dbc98

libcef/browser_impl.cc

@@ -792,6 +792,9 @@ void CefBrowserImpl::UIT_DestroyBrowser()
     webviewhost_.reset();
   }
 
+  // Remove the reference to the window handle.
+  UIT_ClearMainWndHandle();
+
   // Remove the reference added in UIT_CreateBrowser().
   Release();
   
@@ -805,7 +808,9 @@ void CefBrowserImpl::UIT_CloseBrowser()
   if (IsWindowRenderingDisabled()) {
     UIT_DestroyBrowser();
   } else {
-    UIT_CloseView(UIT_GetMainWndHandle());
+    gfx::NativeView view = UIT_GetMainWndHandle();
+    if (view)
+      UIT_CloseView(view);
   }
 }