Add more debugging code to track down RFP duplicate routing ID crashes.

The goal of this CL is to do a DumpWithoutCrashing if we ever send a
proxy creation IPC to the same renderer process more than once.  This
shouldn't ever happen, since even if the proxy becomes non-live after
a process crash and is later recreated, the IPC should go into a newly
respawned renderer process.

Bug: 794625
Change-Id: I6df34d2582645c8c398b9f6b6ce9c87ba772591d
Reviewed-on: https://chromium-review.googlesource.com/1147483Reviewed-by: Charlie Reis <creis@chromium.org>
Commit-Queue: Charlie Reis <creis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#577653}

content/browser/frame_host/render_frame_proxy_host.cc

@@ -207,7 +207,9 @@ bool RenderFrameProxyHost::InitRenderFrameProxy() {
   // Temporary debugging code for https://crbug.com/794625 to see if we're ever
   // sending a message to create a RenderFrameProxy when one already exists.
   // TODO(alexmos): Remove after the investigation.
-  if (render_frame_proxy_created_) {
+  if (GetProcess()->GetProcess().IsValid() &&
+      GetProcess()->GetProcess().Pid() ==
+          pid_of_last_create_message_for_debugging_) {
     SiteInstanceImpl* site_instance =
         static_cast<SiteInstanceImpl*>(site_instance_.get());
     GURL site_url(site_instance->GetSiteURL());
@@ -235,7 +237,7 @@ bool RenderFrameProxyHost::InitRenderFrameProxy() {
       frame_tree_node_->current_replication_state(),
       frame_tree_node_->devtools_frame_token());
 
-  render_frame_proxy_created_ = true;
+  set_render_frame_proxy_created(true);
 
   // For subframes, initialize the proxy's FrameOwnerProperties only if they
   // differ from default values.

content/browser/frame_host/render_frame_proxy_host.h

@@ -139,6 +139,12 @@ class RenderFrameProxyHost
 
   void set_render_frame_proxy_created(bool created) {
     render_frame_proxy_created_ = created;
+    // TODO(alexmos): Temporary instrumentation code; remove after
+    // investigating https://crbug.com/794625.
+    if (created && GetProcess()->GetProcess().IsValid()) {
+      pid_of_last_create_message_for_debugging_ =
+          GetProcess()->GetProcess().Pid();
+    }
   }
 
   // Returns if the RenderFrameProxy for this host is alive.
@@ -176,6 +182,10 @@ class RenderFrameProxyHost
   // True if we have a live RenderFrameProxy for this host.
   bool render_frame_proxy_created_;
 
+  // TODO(alexmos): Remove after investigating https://crbug.com/794625.
+  base::ProcessId pid_of_last_create_message_for_debugging_ =
+      base::kNullProcessId;
+
   // When a RenderFrameHost is in a different process from its parent in the
   // frame tree, this class connects its associated RenderWidgetHostView
   // to this RenderFrameProxyHost, which corresponds to the same frame in the