Battery Status API: add testing support for LayoutTests.

content/shell/renderer/webkit_test_runner.cc

Index: content/shell/renderer/webkit_test_runner.cc
diff --git a/content/shell/renderer/webkit_test_runner.cc b/content/shell/renderer/webkit_test_runner.cc
index ea9946558bc28dda25d5102b4861867c81a8ff14..9c069d0e9e70469f9e49531698d9bc3ec3514e21 100644
--- a/content/shell/renderer/webkit_test_runner.cc
+++ b/content/shell/renderer/webkit_test_runner.cc
@@ -235,6 +235,11 @@ void WebKitTestRunner::resetScreenOrientation() {
   ResetMockScreenOrientation();
 }
 
+void WebKitTestRunner::didChangeBatteryStatus(
+    const blink::WebBatteryStatus& status) {
+  MockBatteryStatusChanged(status);
+}
+
 void WebKitTestRunner::printMessage(const std::string& message) {
   Send(new ShellViewHostMsg_PrintMessage(routing_id(), message));
 }