OOPIF: Support session restore by combining/splitting frame states.

content/browser/frame_host/navigation_entry_impl.cc

 // Copyright 2013 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/frame_host/navigation_entry_impl.h"
 
 #include <queue>
 
 #include "base/metrics/histogram.h"
 #include "base/strings/string_util.h"
 #include "base/strings/utf_string_conversions.h"
 #include "components/url_formatter/url_formatter.h"
 #include "content/common/navigation_params.h"
 #include "content/common/page_state_serialization.h"
 #include "content/common/site_isolation_policy.h"
 #include "content/public/common/content_constants.h"
 #include "content/public/common/url_constants.h"
 #include "ui/gfx/text_elider.h"
 
+using base::UTF16ToUTF8;
+
+namespace content {
+
+namespace {
+
 // Use this to get a new unique ID for a NavigationEntry during construction.
 // The returned ID is guaranteed to be nonzero (which is the "no ID" indicator).
 static int GetUniqueIDInConstructor() {
   static int unique_id_counter = 0;
   return ++unique_id_counter;
 }
 
-namespace content {
+void RecursivelyGenerateFrameEntries(const ExplodedFrameState& state,
+                                     NavigationEntryImpl::TreeNode* node) {
+  node->frame_entry = new FrameNavigationEntry(
+      -1, UTF16ToUTF8(state.target.string()), state.item_sequence_number,
+      state.document_sequence_number, nullptr, GURL(state.url_string.string()),
+      Referrer(GURL(state.referrer.string()), state.referrer_policy));
+
+  node->frame_entry->set_frame_state(state);
+
+  for (const ExplodedFrameState& child_state : state.children) {
+    NavigationEntryImpl::TreeNode* child_node =
+        new NavigationEntryImpl::TreeNode(nullptr);
+    node->children.push_back(child_node);
+    RecursivelyGenerateFrameEntries(child_state, child_node);
+  }
+}
+
+void RecursivelyGenerateFrameState(
+    NavigationEntryImpl::TreeNode* node,
+    ExplodedFrameState* state,
+    std::vector<base::NullableString16>* referenced_files) {
+  // Copy the FrameNavigationEntry's frame state into the destination state.
+  *state = node->frame_entry->frame_state();
+
+  // TODO(creis): Copy the referenced files from frame_entry into
+  // referenced_files (which is from PageState).  Need to implement helper.
+  // ToNullableString16Vector(node->frame_entry->referenced_files(),
+  //                          referenced_files);
+
+  state->children.resize(node->children.size());
+  for (size_t i = 0; i < node->children.size(); ++i) {
+    RecursivelyGenerateFrameState(node->children[i], &state->children[i],
+                                  referenced_files);
+  }
+}
+
+}  // namespace
 
 int NavigationEntryImpl::kInvalidBindings = -1;
 
 NavigationEntryImpl::TreeNode::TreeNode(FrameNavigationEntry* frame_entry)
     : frame_entry(frame_entry) {
 }
 
 NavigationEntryImpl::TreeNode::~TreeNode() {
 }
 
@@ skipping 135 matching lines @@
 void NavigationEntryImpl::SetTitle(const base::string16& title) {
   title_ = title;
   cached_display_title_.clear();
 }
 
 const base::string16& NavigationEntryImpl::GetTitle() const {
   return title_;
 }
 
 void NavigationEntryImpl::SetPageState(const PageState& state) {
-  frame_tree_->frame_entry->set_page_state(state);
+  page_state_ = state;
 
-  if (SiteIsolationPolicy::UseSubframeNavigationEntries()) {
-    // Also get the root ISN and DSN out of the PageState.
-    ExplodedPageState exploded_state;
-    if (!DecodePageState(state.ToEncodedData(), &exploded_state))
-      return;
-    frame_tree_->frame_entry->set_item_sequence_number(
-        exploded_state.top.item_sequence_number);
-    frame_tree_->frame_entry->set_document_sequence_number(
-        exploded_state.top.document_sequence_number);
+  if (!SiteIsolationPolicy::UseSubframeNavigationEntries())
+    return;
+
+  // This should only be called when restoring a NavigationEntry, so there
+  // should be no subframe FrameNavigationEntries yet.
+  DCHECK_EQ(0U, frame_tree_->children.size());
+
+  ExplodedPageState exploded_state;
+  if (!DecodePageState(state.ToEncodedData(), &exploded_state)) {
+    // Give up and set an empty ExplodedFrameState on the main frame.
+    frame_tree_->frame_entry->set_frame_state(ExplodedFrameState());
+    return;
   }
+
+  RecursivelyGenerateFrameEntries(exploded_state.top, frame_tree_.get());
 }
 
 const PageState& NavigationEntryImpl::GetPageState() const {
-  return frame_tree_->frame_entry->page_state();
+  return page_state_;
+}
+
+void NavigationEntryImpl::UpdatePageState() {
+  // When we're using subframe entries, each FrameNavigationEntry has a
+  // frame-specific PageState.  We combine these into an ExplodedPageState tree
+  // and generate a full PageState from it.
+  DCHECK(SiteIsolationPolicy::UseSubframeNavigationEntries());
+  ExplodedPageState exploded_state;
+  RecursivelyGenerateFrameState(frame_tree_.get(), &exploded_state.top,
+                                &exploded_state.referenced_files);
+
+  std::string encoded_data;
+  if (!EncodePageState(exploded_state, &encoded_data)) {
+    page_state_ = PageState();
+    return;
+  }
+
+  page_state_ = PageState::CreateFromEncodedData(encoded_data);
 }
 
 void NavigationEntryImpl::SetPageID(int page_id) {
   page_id_ = page_id;
 }
 
 int32 NavigationEntryImpl::GetPageID() const {
   return page_id_;
 }
 
@@ skipping 302 matching lines @@
   int current_offset_to_send = current_history_list_offset;
   int current_length_to_send = current_history_list_length;
   if (should_clear_history_list()) {
     // Set the history list related parameters to the same values a
     // NavigationController would return before its first navigation. This will
     // fully clear the RenderView's view of the session history.
     pending_offset_to_send = -1;
     current_offset_to_send = -1;
     current_length_to_send = 0;
   }
+
+  // Use the actual PageState in default Chrome, and only send the frame state
+  // in OOPIF modes.
+  PageState page_state = SiteIsolationPolicy::UseSubframeNavigationEntries()
+                             ? PageState()
+                             : GetPageState();
+
   return RequestNavigationParams(
       GetIsOverridingUserAgent(), redirects, GetCanLoadLocalResources(),
-      base::Time::Now(), frame_entry.page_state(), GetPageID(), GetUniqueID(),
-      is_same_document_history_load, has_committed_real_load,
+      base::Time::Now(), page_state, frame_entry.frame_state(), GetPageID(),
+      GetUniqueID(), is_same_document_history_load, has_committed_real_load,
       intended_as_new_entry, pending_offset_to_send, current_offset_to_send,
       current_length_to_send, should_clear_history_list());
 }
 
 void NavigationEntryImpl::ResetForCommit() {
   // Any state that only matters when a navigation entry is pending should be
   // cleared here.
   // TODO(creis): This state should be moved to NavigationRequest once
   // PlzNavigate is enabled.
   SetBrowserInitiatedPostData(nullptr);
@@ skipping 13 matching lines @@
 }
 
 void NavigationEntryImpl::AddOrUpdateFrameEntry(
     FrameTreeNode* frame_tree_node,
     const std::string& frame_unique_name,
     int64 item_sequence_number,
     int64 document_sequence_number,
     SiteInstanceImpl* site_instance,
     const GURL& url,
     const Referrer& referrer,
-    const PageState& page_state) {
+    const ExplodedFrameState& frame_state) {
   // We should already have a TreeNode for the parent node by the time this node
   // commits.  Find it first.
   DCHECK(frame_tree_node->parent());
   NavigationEntryImpl::TreeNode* parent_node =
       FindFrameEntry(frame_tree_node->parent());
   if (!parent_node) {
     // The renderer should not send a commit for a subframe before its parent.
     // TODO(creis): Kill the renderer if we get here.
     return;
   }
 
   // Now check whether we have a TreeNode for the node itself.
   int frame_tree_node_id = frame_tree_node->frame_tree_node_id();
   for (TreeNode* child : parent_node->children) {
     if (child->frame_entry->frame_tree_node_id() == frame_tree_node_id) {
       // Update the existing FrameNavigationEntry (e.g., for replaceState).
       child->frame_entry->UpdateEntry(frame_unique_name, item_sequence_number,
                                       document_sequence_number, site_instance,
-                                      url, referrer, page_state);
+                                      url, referrer, frame_state);
       return;
     }
   }
 
   // No entry exists yet, so create a new one.
   // Unordered list, since we expect to look up entries by frame sequence number
   // or unique name.
   FrameNavigationEntry* frame_entry = new FrameNavigationEntry(
       frame_tree_node_id, frame_unique_name, item_sequence_number,
       document_sequence_number, site_instance, url, referrer);
-  frame_entry->set_page_state(page_state);
+  frame_entry->set_frame_state(frame_state);
   parent_node->children.push_back(
       new NavigationEntryImpl::TreeNode(frame_entry));
 }
 
 FrameNavigationEntry* NavigationEntryImpl::GetFrameEntry(
     FrameTreeNode* frame_tree_node) const {
   NavigationEntryImpl::TreeNode* tree_node = FindFrameEntry(frame_tree_node);
   return tree_node ? tree_node->frame_entry.get() : nullptr;
 }
 
@@ skipping 41 matching lines @@
       return node;
     }
     // Enqueue any children and keep looking.
     for (auto& child : node->children)
       work_queue.push(child);
   }
   return nullptr;
 }
 
 }  // namespace content