Reload Lo-Fi images inline instead of reloading the whole page

For all ImageResource's in the document resources list that
have "q=low" directives in the Chrome-Proxy response header,
clear the old image data and reload with Lo-Fi disabled.

BUG=506252
CQ_INCLUDE_TRYBOTS=tryserver.chromium.linux:linux_site_isolation

Review URL: https://codereview.chromium.org/1624583003

Cr-Commit-Position: refs/heads/master@{#373657}
diff --git a/content/browser/web_contents/web_contents_impl.cc b/content/browser/web_contents/web_contents_impl.cc
index 2af90ae..2d47132 100644
--- a/content/browser/web_contents/web_contents_impl.cc
+++ b/content/browser/web_contents/web_contents_impl.cc
@@ -2341,6 +2341,10 @@
       focused_frame->GetRoutingID(), ignore_cache));
 }
 
+void WebContentsImpl::ReloadLoFiImages() {
+  SendToAllFrames(new FrameMsg_ReloadLoFiImages(MSG_ROUTING_NONE));
+}
+
 void WebContentsImpl::Undo() {
   RenderFrameHost* focused_frame = GetFocusedFrame();
   if (!focused_frame)