OOPIF: Fix CapturePageInfo to only operate on local main frames.

This logic will need to move to the browser process to capture text
from frames that live in other processes.

BUG=346764
TEST=Navigate in an out-of-process iframe and wait 10 seconds.

Review URL: https://codereview.chromium.org/645803002

Cr-Commit-Position: refs/heads/master@{#299138}

chrome/renderer/chrome_render_view_observer.cc

@@ -381,6 +381,13 @@ void ChromeRenderViewObserver::CapturePageInfo(bool preliminary_capture) {
   if (!main_frame)
     return;
 
+  // TODO(creis): Refactor WebFrame::contentAsText to handle RemoteFrames,
+  // likely by moving it to the browser process.  For now, only capture page
+  // info from main frames that are LocalFrames, and ignore their RemoteFrame
+  // children.
+  if (main_frame->isWebRemoteFrame())
+    return;
+
   // Don't index/capture pages that are in view source mode.
   if (main_frame->isViewSourceModeEnabled())
     return;