Fix user agent overridding with PlzNavigate.

content/browser/frame_host/navigation_request.cc

 // Copyright 2014 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 "content/browser/frame_host/navigation_request.h"
 
 #include <utility>
 
 #include "base/memory/ptr_util.h"
 #include "content/browser/appcache/appcache_navigation_handle.h"
@@ skipping 109 matching lines @@
   return true;
 }
 
 // TODO(clamy): This should match what's happening in
 // blink::FrameFetchContext::addAdditionalRequestHeaders.
 void AddAdditionalRequestHeaders(net::HttpRequestHeaders* headers,
                                  const GURL& url,
                                  FrameMsg_Navigate_Type::Value navigation_type,
                                  BrowserContext* browser_context,
                                  const std::string& method,
+                                 const std::string user_agent_override,
                                  FrameTreeNode* frame_tree_node) {
   if (!url.SchemeIsHTTPOrHTTPS())
     return;
 
   bool is_reload =
       navigation_type == FrameMsg_Navigate_Type::RELOAD ||
       navigation_type == FrameMsg_Navigate_Type::RELOAD_BYPASSING_CACHE ||
       navigation_type == FrameMsg_Navigate_Type::RELOAD_ORIGINAL_REQUEST_URL;
   if (is_reload)
     headers->RemoveHeader("Save-Data");
 
   if (GetContentClient()->browser()->IsDataSaverEnabled(browser_context))
     headers->SetHeaderIfMissing("Save-Data", "on");
 
   headers->SetHeaderIfMissing(net::HttpRequestHeaders::kUserAgent,
-                              GetContentClient()->GetUserAgent());
+                              user_agent_override.empty()
+                                  ? GetContentClient()->GetUserAgent()
+                                  : user_agent_override);
 
   // Check whether DevTools wants to override user agent for this request
   // after setting the default user agent.
   std::string devtools_user_agent =
       RenderFrameDevToolsAgentHost::UserAgentOverride(frame_tree_node);
   if (!devtools_user_agent.empty()) {
     headers->SetHeader(net::HttpRequestHeaders::kUserAgent,
                        devtools_user_agent);
   }
 
@@ skipping 163 matching lines @@
     source_site_instance_ =
         frame_tree_node->current_frame_host()->GetSiteInstance();
   }
 
   // Update the load flags with cache information.
   UpdateLoadFlagsWithCacheFlags(&begin_params_.load_flags,
                                 common_params_.navigation_type,
                                 common_params_.method == "POST");
 
   // Add necessary headers that may not be present in the BeginNavigationParams.
+  const std::string user_agent_override =
+      frame_tree_node_->navigator()->GetDelegate()->GetUserAgentOverride();
   net::HttpRequestHeaders headers;
   headers.AddHeadersFromString(begin_params_.headers);
   AddAdditionalRequestHeaders(
       &headers, common_params_.url, common_params_.navigation_type,
       frame_tree_node_->navigator()->GetController()->GetBrowserContext(),
-      common_params.method, frame_tree_node);
+      common_params.method, user_agent_override, frame_tree_node);
   begin_params_.headers = headers.ToString();
 }
 
 NavigationRequest::~NavigationRequest() {
 }
 
 void NavigationRequest::BeginNavigation() {
   DCHECK(!loader_);
   DCHECK(state_ == NOT_STARTED || state_ == WAITING_FOR_RENDERER_RESPONSE);
   state_ = STARTED;
@@ skipping 424 matching lines @@
   DCHECK_EQ(request_params_.has_user_gesture, begin_params_.has_user_gesture);
 
   render_frame_host->CommitNavigation(response_.get(), std::move(body_),
                                       common_params_, request_params_,
                                       is_view_source_);
 
   frame_tree_node_->ResetNavigationRequest(true);
 }
 
 }  // namespace content