Fix for WebView accessible resources.

extensions/browser/guest_view/web_view/web_view_guest.cc

Index: extensions/browser/guest_view/web_view/web_view_guest.cc
diff --git a/extensions/browser/guest_view/web_view/web_view_guest.cc b/extensions/browser/guest_view/web_view/web_view_guest.cc
index da15b9fa92d4571d3a5dc28e216887b8c6b37452..15dacf4893a80bc2ba5f31b1d8fff341841991f6 100644
--- a/extensions/browser/guest_view/web_view/web_view_guest.cc
+++ b/extensions/browser/guest_view/web_view/web_view_guest.cc
@@ -48,6 +48,7 @@
 #include "extensions/browser/guest_view/web_view/web_view_renderer_state.h"
 #include "extensions/common/constants.h"
 #include "extensions/common/extension_messages.h"
+#include "extensions/common/manifest_constants.h"
 #include "extensions/strings/grit/extensions_strings.h"
 #include "ipc/ipc_message_macros.h"
 #include "net/base/escape.h"
@@ -58,6 +59,7 @@
 using base::UserMetricsAction;
 using content::GlobalRequestID;
 using content::RenderFrameHost;
+using content::RenderProcessHost;
 using content::ResourceType;
 using content::StoragePartition;
 using content::WebContents;
@@ -264,6 +266,18 @@ bool WebViewGuest::GetGuestPartitionConfigForSite(
 }
 
 // static
+std::string WebViewGuest::GetPartitionID(
+    const RenderProcessHost* render_process_host) {
+  WebViewRendererState* renderer_state = WebViewRendererState::GetInstance();
+  int process_id = render_process_host->GetID();
+  std::string partition_id;
+  if (renderer_state->IsGuest(process_id))
+    renderer_state->GetPartitionID(process_id, &partition_id);

[not at google - send to devlin, 2015/08/31 18:31:44]

There is a threading mismatch here. WebViewRendererState says onto to access it
on the IO thread, but I see UI thread accessors.

[paulmeyer, 2015/08/31 21:40:08]

You may have been looking at an out-of-date version of WebViewRendererState. It
now allows access from UI or IO threads (as of last week).

[not at google - send to devlin, 2015/08/31 21:52:51]

I'm not looking at an old version, I'm looking at git trunk:

https://chromium.googlesource.com/chromium/src/+/master/extensions/browser/gu...

That file says the equivalent of "call on IO thread" 5 times, in this case:

  // Looks up the partition info for the embedder <webview> for a given guest
  // process. Called on the IO thread.

[paulmeyer, 2015/09/02 13:43:57]

Oh, I see. Those comments are stale, so I'll remove them.

+
+  return partition_id;
+}
+
+// static
 const char WebViewGuest::Type[] = "webview";
 
 // static