PlzNavigate: provide the FrameTreeNode ID to the network stack

content/browser/download/download_request_handle.cc

Index: content/browser/download/download_request_handle.cc
diff --git a/content/browser/download/download_request_handle.cc b/content/browser/download/download_request_handle.cc
index 32c5b987799d510d79fb6e12c4327784498fdd86..6e319d3abee213eac6300b25abaf661bea3b4a53 100644
--- a/content/browser/download/download_request_handle.cc
+++ b/content/browser/download/download_request_handle.cc
@@ -5,11 +5,15 @@
 #include "content/browser/download/download_request_handle.h"
 
 #include "base/bind.h"
+#include "base/command_line.h"
 #include "base/strings/stringprintf.h"
+#include "content/browser/frame_host/navigator.h"
+#include "content/browser/frame_host/render_frame_host_impl.h"
 #include "content/browser/renderer_host/render_view_host_impl.h"
 #include "content/browser/web_contents/web_contents_impl.h"
 #include "content/public/browser/browser_context.h"
 #include "content/public/browser/browser_thread.h"
+#include "content/public/common/content_switches.h"
 
 namespace content {
 
@@ -19,31 +23,63 @@ DownloadRequestHandle::~DownloadRequestHandle() {
 DownloadRequestHandle::DownloadRequestHandle()
     : child_id_(-1),
       render_view_id_(-1),
-      request_id_(-1) {
+      request_id_(-1),
+      frame_tree_node_id_(-1) {
 }
 
 DownloadRequestHandle::DownloadRequestHandle(
     const base::WeakPtr<DownloadResourceHandler>& handler,
     int child_id,
     int render_view_id,
-    int request_id)
+    int request_id,
+    int frame_tree_node_id)
     : handler_(handler),
       child_id_(child_id),
       render_view_id_(render_view_id),
-      request_id_(request_id) {
+      request_id_(request_id),
+      frame_tree_node_id_(frame_tree_node_id) {
   DCHECK(handler_.get());
 }
 
 WebContents* DownloadRequestHandle::GetWebContents() const {
+  // PlzNavigate: if a FrameTreeNodeID was provided, use it to return the
+  // WebContents.
+  // TODO(davidben): This logic should be abstracted within the ResourceLoader
+  // stack. https://crbug.com/376003
+  if (base::CommandLine::ForCurrentProcess()->HasSwitch(
+          switches::kEnableBrowserSideNavigation)) {
+    FrameTreeNode* frame_tree_node =
+        FrameTreeNode::GloballyFindByID(frame_tree_node_id_);
+    if (frame_tree_node) {
+      return WebContentsImpl::FromFrameTreeNode(frame_tree_node);
+    }
+  }
+
   RenderViewHostImpl* render_view_host =
       RenderViewHostImpl::FromID(child_id_, render_view_id_);
   if (!render_view_host)
-    return NULL;
+    return nullptr;
 
   return render_view_host->GetDelegate()->GetAsWebContents();
 }
 
 DownloadManager* DownloadRequestHandle::GetDownloadManager() const {
+  // PlzNavigate: if a FrameTreeNodeID was provided, use it to return the
+  // DownloadManager.
+  // TODO(davidben): This logic should be abstracted within the ResourceLoader
+  // stack. https://crbug.com/376003
+  if (base::CommandLine::ForCurrentProcess()->HasSwitch(
+          switches::kEnableBrowserSideNavigation)) {
+    FrameTreeNode* frame_tree_node =
+        FrameTreeNode::GloballyFindByID(frame_tree_node_id_);
+    if (frame_tree_node) {
+      BrowserContext* context =
+          frame_tree_node->navigator()->GetController()->GetBrowserContext();
+      if (context)
+        return BrowserContext::GetDownloadManager(context);
+    }
+  }
+
   RenderViewHostImpl* rvh = RenderViewHostImpl::FromID(
       child_id_, render_view_id_);
   if (rvh == NULL)