Fix page zoom to be frame-centric for out-of-process frames.

content/renderer/render_frame_impl.cc

Index: content/renderer/render_frame_impl.cc
diff --git a/content/renderer/render_frame_impl.cc b/content/renderer/render_frame_impl.cc
index e4ee832d5c05e5166cda0e4ad55d8d380f48d924..3fe08ce140e30e54b24aacac9f0a7e0dd002a6e5 100644
--- a/content/renderer/render_frame_impl.cc
+++ b/content/renderer/render_frame_impl.cc
@@ -4566,6 +4566,8 @@ void RenderFrameImpl::SendDidCommitProvisionalLoad(
     DCHECK(!navigation_state->request_params().should_clear_history_list);
     params.history_list_was_cleared = false;
     params.report_type = FrameMsg_UILoadMetricsReportType::NO_REPORT;
+    // Subframes should match the zoom level of the main frame.
+    render_view_->webview()->setZoomLevel(render_view_->page_zoom_level());
   }
 
   // This message needs to be sent before any of allowScripts(),