Revert of [Offline pages] Integrate snapshot controller fully into background loader.

chrome/browser/android/offline_pages/background_loader_offliner.cc

Index: chrome/browser/android/offline_pages/background_loader_offliner.cc
diff --git a/chrome/browser/android/offline_pages/background_loader_offliner.cc b/chrome/browser/android/offline_pages/background_loader_offliner.cc
index 5a15362940c38295967db1f5f00b5335dd0cd064..6ccd766b020e6031d7bef1c4b247235233143674 100644
--- a/chrome/browser/android/offline_pages/background_loader_offliner.cc
+++ b/chrome/browser/android/offline_pages/background_loader_offliner.cc
@@ -14,7 +14,6 @@
 #include "components/offline_pages/core/offline_page_model.h"
 #include "content/public/browser/browser_context.h"
 #include "content/public/browser/navigation_handle.h"
-#include "content/public/browser/render_frame_host.h"
 #include "content/public/browser/web_contents.h"
 #include "content/public/browser/web_contents_user_data.h"
 
@@ -22,7 +21,6 @@
 
 namespace {
 const long kOfflinePageDelayMs = 2000;
-const long kOfflineDomContentLoadedMs = 25000;
 
 class OfflinerData : public content::WebContentsUserData<OfflinerData> {
  public:
@@ -155,6 +153,9 @@
   if (!loader_)
     ResetState();
 
+  // Invalidate ptrs for all delayed/saving tasks.
+  weak_ptr_factory_.InvalidateWeakPtrs();
+
   // Track copy of pending request.
   pending_request_.reset(new SavePageRequest(request));
   completion_callback_ = completion_callback;
@@ -168,16 +169,12 @@
   // Load page attempt.
   loader_.get()->LoadPage(request.url());
 
-  snapshot_controller_.reset(
-      new SnapshotController(base::ThreadTaskRunnerHandle::Get(), this,
-                             kOfflineDomContentLoadedMs, page_delay_ms_));
-
   return true;
 }
 
 void BackgroundLoaderOffliner::Cancel(const CancelCallback& callback) {
   // TODO(chili): We are not able to cancel a pending
-  // OfflinePageModel::SaveSnapshot() operation. We will notify caller that
+  // OfflinePageModel::SavePage() operation. We will notify caller that
   // cancel completed once the SavePage operation returns.
   if (!pending_request_) {
     callback.Run(0LL);
@@ -201,20 +198,21 @@
   return false;
 }
 
-void BackgroundLoaderOffliner::DocumentLoadedInFrame(
-    content::RenderFrameHost* render_host) {
-  // Inform snapshot controller if in main frame.
-  if (!render_host->GetParent())
-    snapshot_controller_->DocumentAvailableInMainFrame();
-}
-
 void BackgroundLoaderOffliner::DidStopLoading() {
   if (!pending_request_.get()) {
     DVLOG(1) << "DidStopLoading called even though no pending request.";
     return;
   }
 
-  snapshot_controller_->DocumentOnLoadCompletedInMainFrame();
+  // Invalidate ptrs for any ongoing save operation.
+  weak_ptr_factory_.InvalidateWeakPtrs();
+
+  // Post SavePage task with 2 second delay.
+  base::ThreadTaskRunnerHandle::Get()->PostDelayedTask(
+      FROM_HERE,
+      base::Bind(&BackgroundLoaderOffliner::SavePage,
+                 weak_ptr_factory_.GetWeakPtr()),
+      base::TimeDelta::FromMilliseconds(page_delay_ms_));
 }
 
 void BackgroundLoaderOffliner::RenderProcessGone(
@@ -288,6 +286,18 @@
         page_load_state_ = RETRIABLE;
     }
   }
+
+  // If the document is not the same invalidate any pending save tasks.
+  //
+  // Downloads or 204/205 response codes do not commit (no new navigation)
+  // Same-Document (committed) navigations are:
+  // - reference fragment navigations
+  // - pushState/replaceState
+  // - same document history navigation
+  if (navigation_handle->HasCommitted() &&
+      !navigation_handle->IsSameDocument()) {
+    weak_ptr_factory_.InvalidateWeakPtrs();
+  }
 }
 
 void BackgroundLoaderOffliner::SetPageDelayForTest(long delay_ms) {
@@ -301,7 +311,7 @@
   }
 }
 
-void BackgroundLoaderOffliner::StartSnapshot() {
+void BackgroundLoaderOffliner::SavePage() {
   if (!pending_request_.get()) {
     DVLOG(1) << "Pending request was cleared during delay.";
     return;
@@ -372,8 +382,6 @@
   }
 
   save_state_ = NONE;
-  // Prevent snapshot controller from making any more snapshots.
-  snapshot_controller_->Stop();
 
   Offliner::RequestStatus save_status;
   if (save_result == SavePageResult::SUCCESS)
@@ -386,7 +394,6 @@
 
 void BackgroundLoaderOffliner::ResetState() {
   pending_request_.reset();
-  snapshot_controller_.reset();
   page_load_state_ = SUCCESS;
   network_bytes_ = 0LL;
   // TODO(chili): Remove after RequestCoordinator can handle multiple offliners.