[Offline pages] Change SnapshotController interface for renovations.

Adds methods to SnapshotController and SnapshotController::Client for
the renovation framework. Also adds basic implementations to all
SnapshotController::Client implementors. This doesn't change the
behavior of the SnapshotController yet.

Design doc:
https://docs.google.com/document/d/1WuwRJaxBKAwVpeAHG0xhq5uRxMTB-j4LFleT4QEqANU

Bug: 736933
Change-Id: Iee15c54fa4524b1c09a87f6e6c43a8df8ea630ee
Reviewed-on: https://chromium-review.googlesource.com/580692Reviewed-by: Peter Williamson <petewil@chromium.org>
Reviewed-by: Dmitry Titov <dimich@chromium.org>
Reviewed-by: Yafei Duan <romax@chromium.org>
Commit-Queue: Collin Baker <collinbaker@google.com>
Cr-Commit-Position: refs/heads/master@{#488696}

chrome/browser/offline_pages/background_loader_offliner.cc

@@ -469,6 +469,11 @@ void BackgroundLoaderOffliner::StartSnapshot() {
                  weak_ptr_factory_.GetWeakPtr()));
 }
 
+void BackgroundLoaderOffliner::RunRenovations() {
+  // TODO(collinbaker): run renovations from here.
+  snapshot_controller_->RenovationsCompleted();
+}
+
 void BackgroundLoaderOffliner::OnPageSaved(SavePageResult save_result,
                                            int64_t offline_id) {
   if (!pending_request_)

chrome/browser/offline_pages/background_loader_offliner.h

@@ -69,6 +69,7 @@ class BackgroundLoaderOffliner : public Offliner,
 
   // SnapshotController::Client implementation.
   void StartSnapshot() override;
+  void RunRenovations() override;
 
   void SetSnapshotControllerForTest(
       std::unique_ptr<SnapshotController> controller);

chrome/browser/offline_pages/prerendering_loader.cc

@@ -195,6 +195,10 @@ void PrerenderingLoader::StartSnapshot() {
   HandleLoadEvent();
 }
 
+void PrerenderingLoader::RunRenovations() {
+  snapshot_controller_->RenovationsCompleted();
+}
+
 bool PrerenderingLoader::IsLowbarMet() {
   return is_lowbar_met_;
 }

chrome/browser/offline_pages/prerendering_loader.h

@@ -81,6 +81,7 @@ class PrerenderingLoader : public PrerenderAdapter::Observer,
 
   // SnapshotController::Client implementation:
   void StartSnapshot() override;
+  void RunRenovations() override;
 
   // Returns true if the lowbar of snapshotting a page is met.
   virtual bool IsLowbarMet();

chrome/browser/offline_pages/recent_tab_helper.cc

@@ -374,6 +374,10 @@ void RecentTabHelper::StartSnapshot() {
   snapshot_controller_->PendingSnapshotCompleted();
 }
 
+void RecentTabHelper::RunRenovations() {
+  snapshot_controller_->RenovationsCompleted();
+}
+
 void RecentTabHelper::SaveSnapshotForDownloads(bool replace_latest) {
   DCHECK_NE(PageQuality::POOR, snapshot_controller_->current_page_quality());
 

chrome/browser/offline_pages/recent_tab_helper.h

@@ -48,6 +48,7 @@ class RecentTabHelper
 
   // SnapshotController::Client
   void StartSnapshot() override;
+  void RunRenovations() override;
 
   // Delegate that is used by RecentTabHelper to get external dependencies.
   // Default implementation lives in .cc file, while tests provide an override.

components/offline_pages/core/snapshot_controller.cc

@@ -94,6 +94,11 @@ void SnapshotController::PendingSnapshotCompleted() {
   state_ = State::READY;
 }
 
+void SnapshotController::RenovationsCompleted() {
+  // Do nothing for now.
+  // TODO(collinbaker): delay snapshot until this signal is received.
+}
+
 void SnapshotController::DocumentAvailableInMainFrame() {
   if (document_available_triggers_snapshot_) {
     DCHECK_EQ(PageQuality::POOR, current_page_quality_);

components/offline_pages/core/snapshot_controller.h

@@ -56,6 +56,11 @@ class SnapshotController {
     // it is assumed that later snapshots are better then previous.
     virtual void StartSnapshot() = 0;
 
+    // Invoked when the page is sufficiently loaded for running
+    // renovations. The client should call the RenovationsCompleted()
+    // when they finish.
+    virtual void RunRenovations() = 0;
+
    protected:
     virtual ~Client() {}
   };
@@ -91,6 +96,9 @@ class SnapshotController {
   // now completed (so the next one can be started).
   void PendingSnapshotCompleted();
 
+  // The Client calls this when renovations have completed.
+  void RenovationsCompleted();
+
   // Invoked from WebContentObserver::DocumentAvailableInMainFrame
   void DocumentAvailableInMainFrame();
 

components/offline_pages/core/snapshot_controller_unittest.cc

@@ -29,6 +29,7 @@ class SnapshotControllerTest : public testing::Test,
 
   // SnapshotController::Client
   void StartSnapshot() override;
+  void RunRenovations() override;
 
   // Utility methods.
   // Runs until all of the tasks that are not delayed are gone from the task
@@ -66,6 +67,10 @@ void SnapshotControllerTest::StartSnapshot() {
   snapshot_count_++;
 }
 
+void SnapshotControllerTest::RunRenovations() {
+  controller_->RenovationsCompleted();
+}
+
 void SnapshotControllerTest::PumpLoop() {
   task_runner_->RunUntilIdle();
 }