DevTools: Extenstions: use request.contentEncoded for GetRequestContent

BUG=309710

Review URL: https://codereview.chromium.org/652813005

git-svn-id: svn://svn.chromium.org/blink/trunk@184351 bbb929c8-8fbe-4397-9dbb-9b2b20218538

third_party/WebKit/Source/devtools/front_end/extensions/ExtensionServer.js

@@ -560,8 +560,13 @@ WebInspector.ExtensionServer.prototype = {
          */
         function onContentAvailable(content)
         {
+            var contentEncoded = false;
+            if (contentProvider instanceof WebInspector.Resource)
+                contentEncoded = contentProvider.contentEncoded;
+            if (contentProvider instanceof WebInspector.NetworkRequest)
+                contentEncoded = contentProvider.contentEncoded;
             var response = {
-                encoding: (content === null) || contentProvider.contentType().isTextType() ? "" : "base64",
+                encoding: contentEncoded && content ? "base64" : "",
                 content: content
             };
             this._dispatchCallback(message.requestId, port, response);