Fixing activation states from the new launcher. Also adding a whole bunch of unit tests for the new…

chrome/browser/ui/views/frame/browser_view.cc

Index: chrome/browser/ui/views/frame/browser_view.cc
diff --git a/chrome/browser/ui/views/frame/browser_view.cc b/chrome/browser/ui/views/frame/browser_view.cc
index a9ae54db735e788cbf0ca75f07b00e477a07b553..348db6ce3d4d5fbf945925d470c27543b914dd73 100644
--- a/chrome/browser/ui/views/frame/browser_view.cc
+++ b/chrome/browser/ui/views/frame/browser_view.cc
@@ -642,6 +642,11 @@ bool BrowserView::IsAlwaysOnTop() const {
 }
 
 gfx::NativeWindow BrowserView::GetNativeWindow() {
+  // While the browser destruction is going on, the widget can already be gone,
+  // but utility functions like FindBrowserWithWindow will come here and crash.
+  // We short circuit therefore.
+  if (!GetWidget())
+    return NULL;
   return GetWidget()->GetTopLevelWidget()->GetNativeWindow();
 }