Remove all blimp engine code

blimp/engine/session/page_load_tracker.cc

-// Copyright 2016 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 "blimp/engine/session/page_load_tracker.h"
-
-#include "content/public/browser/navigation_handle.h"
-#include "content/public/browser/render_widget_host_view.h"
-
-namespace blimp {
-namespace engine {
-
-namespace {
-
-bool ShouldIgnoreNavigation(content::NavigationHandle* navigation_handle) {
-  // We change the progress bar for main frame navigations only.
-  if (!navigation_handle->IsInMainFrame())
-    return true;
-
-  // Same page navigations don't need to trigger a progress bar update.
-  if (navigation_handle->IsSamePage())
-    return true;
-
-  return false;
-}
-
-}  // namespace
-
-PageLoadTracker::PageLoadTracker(content::WebContents* web_contents,
-                                 PageLoadTrackerClient* client)
-    : client_(client) {
-  DCHECK(web_contents);
-  Observe(web_contents);
-}
-
-PageLoadTracker::~PageLoadTracker() {}
-
-void PageLoadTracker::DidStartNavigation(
-    content::NavigationHandle* navigation_handle) {
-  if (ShouldIgnoreNavigation(navigation_handle))
-    return;
-
-  // Cancel any pending callbacks for the previous navigation. We will send an
-  // update based on the progress of this navigation.
-  did_paint_after_navigation_callback_.Cancel();
-  client_->SendPageLoadStatusUpdate(PageLoadStatus::LOADING);
-}
-
-void PageLoadTracker::DidFinishNavigation(
-    content::NavigationHandle* navigation_handle) {
-  if (ShouldIgnoreNavigation(navigation_handle))
-    return;
-
-  if (navigation_handle->HasCommitted()) {
-    // Make sure that at least one compositor content update after the
-    // navigation commits is sent to the client.
-    // Note that a visual state update in our case implies that this callback
-    // will be invoked after the update is queued to be sent to the client.
-    did_paint_after_navigation_callback_.Reset(
-        base::Bind(&PageLoadTracker::DidPaintAfterNavigationCommitted,
-                   base::Unretained(this)));
-    navigation_handle->GetRenderFrameHost()->InsertVisualStateCallback(
-        did_paint_after_navigation_callback_.callback());
-  } else {
-    // Inform the client to update the progress bar right away.
-    client_->SendPageLoadStatusUpdate(PageLoadStatus::LOADED);
-  }
-}
-
-void PageLoadTracker::DidPaintAfterNavigationCommitted(bool result) {
-  client_->SendPageLoadStatusUpdate(PageLoadStatus::LOADED);
-}
-
-}  // namespace engine
-}  // namespace blimp