Avoid GURL allocations/copies/frees in RenderFrameImpl::willSendRequest

chrome/renderer/chrome_content_renderer_client.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/renderer/chrome_content_renderer_client.h"
 
 #include <memory>
 #include <utility>
 
 #include "base/command_line.h"
@@ skipping 1104 matching lines @@
   if (should_fork)
     return true;
 #endif  // defined(ENABLE_EXTENSIONS)
 
   return false;
 }
 
 bool ChromeContentRendererClient::WillSendRequest(
     WebFrame* frame,
     ui::PageTransition transition_type,
-    const GURL& url,
-    const GURL& first_party_for_cookies,
+    const blink::WebURL& url,
     GURL* new_url) {
-  // Check whether the request should be allowed. If not allowed, we reset the
-  // URL to something invalid to prevent the request and cause an error.
+// Check whether the request should be allowed. If not allowed, we reset the
+// URL to something invalid to prevent the request and cause an error.
 #if defined(ENABLE_EXTENSIONS)
   if (ChromeExtensionsRendererClient::GetInstance()->WillSendRequest(
           frame, transition_type, url, new_url)) {
     return true;
   }
 #endif
 
+  // Early exit before fetching the RenderView or SearchBox.

[Devlin, 2016/10/31 15:17:39]

optional nit: This comment doesn't seem to add much value (as it just describes
the code).  I'd suggest removing it, but up to you.

[Charlie Harrison, 2016/10/31 15:46:13]

Done.

+  if (!url.protocolIs(chrome::kChromeSearchScheme))
+    return false;
+
   const content::RenderView* render_view =
       content::RenderView::FromWebView(frame->view());
   SearchBox* search_box = SearchBox::Get(render_view);
-  if (search_box && url.SchemeIs(chrome::kChromeSearchScheme)) {
+  if (search_box) {
+    // Note: this GURL copy could be avoided if host() were added to WebURL.
+    GURL gurl(url);
     SearchBox::ImageSourceType type = SearchBox::NONE;
-    if (url.host() == chrome::kChromeUIFaviconHost)
+    if (gurl.host() == chrome::kChromeUIFaviconHost)
       type = SearchBox::FAVICON;
-    else if (url.host() == chrome::kChromeUILargeIconHost)
+    else if (gurl.host() == chrome::kChromeUILargeIconHost)
       type = SearchBox::LARGE_ICON;
-    else if (url.host() == chrome::kChromeUIFallbackIconHost)
+    else if (gurl.host() == chrome::kChromeUIFallbackIconHost)
       type = SearchBox::FALLBACK_ICON;
-    else if (url.host() == chrome::kChromeUIThumbnailHost)
+    else if (gurl.host() == chrome::kChromeUIThumbnailHost)
       type = SearchBox::THUMB;
 
     if (type != SearchBox::NONE)
       return search_box->GenerateImageURLFromTransientURL(url, type, new_url);
   }
 
   return false;
 }
 
 bool ChromeContentRendererClient::IsPrefetchOnly(
@@ skipping 327 matching lines @@
 
   url::Replacements<char> r;
   r.SetPath(path.c_str(), url::Component(0, path.length()));
 
   if (result == internal::NUM_PLUGIN_ERROR)
     result = invalid_url ? internal::SUCCESS_PARAMS_REWRITE : internal::SUCCESS;
 
   RecordYouTubeRewriteUMA(result);
   return corrected_url.ReplaceComponents(r);
 }