Proof of concept implementation of context based history filtering.

content/browser/web_contents/web_contents_impl.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/browser/web_contents/web_contents_impl.h"
 
 #include <utility>
 
 #include "base/command_line.h"
 #include "base/lazy_instance.h"
@@ skipping 2030 matching lines @@
 
 void WebContentsImpl::Cut() {
   RenderFrameHost* focused_frame = GetFocusedFrame();
   if (!focused_frame)
     return;
 
   focused_frame->Send(new InputMsg_Cut(focused_frame->GetRoutingID()));
   RecordAction(base::UserMetricsAction("Cut"));
 }
 
+void WebContentsImpl::Print() {
+  FOR_EACH_OBSERVER(WebContentsObserver, observers_,
+                    SetHistoryContext(controller_.GetLastCommittedEntry(), 3));
+  printf("\nPrint\n");
+}
+
+void WebContentsImpl::SaveImage() {
+  FOR_EACH_OBSERVER(WebContentsObserver, observers_,
+                    SetHistoryContext(controller_.GetLastCommittedEntry(), 2));
+  printf("\nSave Image\n");
+}
+
 void WebContentsImpl::Copy() {
   RenderFrameHost* focused_frame = GetFocusedFrame();
   if (!focused_frame)
     return;
 
   focused_frame->Send(new InputMsg_Copy(focused_frame->GetRoutingID()));
   RecordAction(base::UserMetricsAction("Copy"));
+  FOR_EACH_OBSERVER(WebContentsObserver, observers_,
+                    SetHistoryContext(controller_.GetLastCommittedEntry(), 1));
+  printf("\nCopy\n");
 }
 
 void WebContentsImpl::CopyToFindPboard() {
 #if defined(OS_MACOSX)
   RenderFrameHost* focused_frame = GetFocusedFrame();
   if (!focused_frame)
     return;
 
   // Windows/Linux don't have the concept of a find pasteboard.
   focused_frame->Send(
@@ skipping 1072 matching lines @@
 
   if (has_video) {
     AddMediaPlayerEntry(player_cookie, &active_video_players_);
 
     // If we're not hidden and have just created a player, create a blocker.
     if (!video_power_save_blocker_ && !IsHidden())
       CreateVideoPowerSaveBlocker();
   }
 
   FOR_EACH_OBSERVER(WebContentsObserver, observers_, MediaStartedPlaying());
+  printf("\nPlaying media\n");
+  FOR_EACH_OBSERVER(WebContentsObserver, observers_,
+                    SetHistoryContext(controller_.GetLastCommittedEntry(), 4));
 }
 
 void WebContentsImpl::OnMediaPausedNotification(int64 player_cookie) {
   RemoveMediaPlayerEntry(player_cookie, &active_audio_players_);
   RemoveMediaPlayerEntry(player_cookie, &active_video_players_);
   MaybeReleasePowerSaveBlockers();
 
   FOR_EACH_OBSERVER(WebContentsObserver, observers_, MediaPaused());
 }
 
@@ skipping 1262 matching lines @@
   node->render_manager()->ResumeResponseDeferredAtStart();
 }
 
 void WebContentsImpl::SetForceDisableOverscrollContent(bool force_disable) {
   force_disable_overscroll_content_ = force_disable;
   if (view_)
     view_->SetOverscrollControllerEnabled(CanOverscrollContent());
 }
 
 }  // namespace content