Make sure only platform app support <webview> tag

chrome/renderer/extensions/dispatcher.cc

Index: chrome/renderer/extensions/dispatcher.cc
diff --git a/chrome/renderer/extensions/dispatcher.cc b/chrome/renderer/extensions/dispatcher.cc
index 887a26df22a8931c14243bb13e37ebe5eeeae364..3366165da50be5db0d56309f27d19908e5537bc1 100644
--- a/chrome/renderer/extensions/dispatcher.cc
+++ b/chrome/renderer/extensions/dispatcher.cc
@@ -981,7 +981,11 @@ void Dispatcher::DidCreateScriptContext(
   if (IsWithinPlatformApp(frame))
     module_system->Require("platformApp");
 
-  if (context_type == Feature::BLESSED_EXTENSION_CONTEXT) {
+  // Only platform app need to support <webview> tag, "webView" and

[Charlie Reis, 2013/03/18 15:16:05]

Please fix typos:
Only platform apps support the <webview> tag, because the "webView" and

+  // "denyWebView" modules will effect the performace of the DOM modification

[Charlie Reis, 2013/03/18 15:16:05]

nit: will effect -> affect
nit: performance of DOM modifications

+  // (http://crbug.com/196453).
+  if (context_type == Feature::BLESSED_EXTENSION_CONTEXT &&
+       IsWithinPlatformApp(frame)) {

[PhistucK, 2013/03/18 17:50:41]

Just driving by -
Maybe cache the result of IsWithinPlatformApp(frame) in a variable and save a
microsecond? It is called a couple of lines prior to this line as well.

(I am not a C++ guy)

     // Note: setting up the WebView class here, not the chrome.webview API.
     // The API will be automatically set up when first used.
     if (extension->HasAPIPermission(APIPermission::kWebView)) {