Fix incorrect DCHECK in task manager's WebContentsEntry.

content/public/test/browser_test_utils.h

Index: content/public/test/browser_test_utils.h
diff --git a/content/public/test/browser_test_utils.h b/content/public/test/browser_test_utils.h
index c5219e9cf624fd8ecf5bfc7149a948be2d4b5f4d..1b063f643f397507953fef7c3f4f46bb0f9164c4 100644
--- a/content/public/test/browser_test_utils.h
+++ b/content/public/test/browser_test_utils.h
@@ -112,6 +112,11 @@ void WaitForResizeComplete(WebContents* web_contents);
 // Causes the specified web_contents to crash. Blocks until it is crashed.
 void CrashTab(WebContents* web_contents);
 
+// Causes the specified web_contents to issue an OnUnresponsiveRenderer event
+// to its observers.
+void SimulateUnresponsiveRenderer(WebContents* web_contents,
+                                  RenderWidgetHost* widget);
+
 // Simulates clicking at the center of the given tab asynchronously; modifiers
 // may contain bits from WebInputEvent::Modifiers.
 void SimulateMouseClick(WebContents* web_contents,