Remove the is_loading_ field from WebContentsImpl

content/browser/frame_host/frame_tree.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/frame_tree.h"
 
 #include <stddef.h>
 
 #include <queue>
 #include <utility>
@@ skipping 61 matching lines @@
   return NodeIterator(tree_->root(), node_to_skip_);
 }
 
 FrameTree::NodeIterator FrameTree::NodeRange::end() {
   return NodeIterator(nullptr, nullptr);
 }
 
 FrameTree::NodeRange::NodeRange(FrameTree* tree, FrameTreeNode* node_to_skip)
     : tree_(tree), node_to_skip_(node_to_skip) {}
 
+FrameTree::ConstNodeIterator::~ConstNodeIterator() {}
+
+FrameTree::ConstNodeIterator& FrameTree::ConstNodeIterator::operator++() {
+  for (size_t i = 0; i < current_node_->child_count(); ++i) {
+    const FrameTreeNode* child = current_node_->child_at(i);
+    queue_.push(child);
+  }
+
+  if (!queue_.empty()) {
+    current_node_ = queue_.front();
+    queue_.pop();
+  } else {
+    current_node_ = nullptr;
+  }
+
+  return *this;
+}
+
+bool FrameTree::ConstNodeIterator::operator==(
+    const ConstNodeIterator& rhs) const {
+  return current_node_ == rhs.current_node_;
+}
+
+FrameTree::ConstNodeIterator::ConstNodeIterator(
+    const FrameTreeNode* starting_node)
+    : current_node_(starting_node) {}
+
+FrameTree::ConstNodeIterator FrameTree::ConstNodeRange::begin() {
+  return ConstNodeIterator(tree_->root());
+}
+
+FrameTree::ConstNodeIterator FrameTree::ConstNodeRange::end() {
+  return ConstNodeIterator(nullptr);
+}
+
+FrameTree::ConstNodeRange::ConstNodeRange(const FrameTree* tree)
+    : tree_(tree) {}
+
 FrameTree::FrameTree(Navigator* navigator,
                      RenderFrameHostDelegate* render_frame_delegate,
                      RenderViewHostDelegate* render_view_delegate,
                      RenderWidgetHostDelegate* render_widget_delegate,
                      RenderFrameHostManager::Delegate* manager_delegate)
     : render_frame_delegate_(render_frame_delegate),
       render_view_delegate_(render_view_delegate),
       render_widget_delegate_(render_widget_delegate),
       manager_delegate_(manager_delegate),
       root_(new FrameTreeNode(this,
@@ skipping 56 matching lines @@
 }
 
 FrameTree::NodeRange FrameTree::Nodes() {
   return NodesExcept(nullptr);
 }
 
 FrameTree::NodeRange FrameTree::NodesExcept(FrameTreeNode* node_to_skip) {
   return NodeRange(this, node_to_skip);
 }
 
+FrameTree::ConstNodeRange FrameTree::ConstNodes() const {
+  return ConstNodeRange(this);
+}
+
 bool FrameTree::AddFrame(
     FrameTreeNode* parent,
     int process_id,
     int new_routing_id,
     blink::WebTreeScopeType scope,
     const std::string& frame_name,
     blink::WebSandboxFlags sandbox_flags,
     const blink::WebFrameOwnerProperties& frame_owner_properties) {
   CHECK_NE(new_routing_id, MSG_ROUTING_NONE);
 
@@ skipping 249 matching lines @@
   // Notify the WebContents.
   root_->navigator()->GetDelegate()->DidChangeLoadProgress();
 }
 
 void FrameTree::ResetLoadProgress() {
   for (FrameTreeNode* node : Nodes())
     node->reset_loading_progress();
   load_progress_ = 0.0;
 }
 
-bool FrameTree::IsLoading() {
-  for (FrameTreeNode* node : Nodes()) {
+bool FrameTree::IsLoading() const {
+  for (const FrameTreeNode* node : ConstNodes()) {
     if (node->IsLoading())
       return true;
   }
   return false;
 }
 
 void FrameTree::ReplicatePageFocus(bool is_focused) {
   std::set<SiteInstance*> frame_tree_site_instances =
       CollectSiteInstances(this);
 
@@ skipping 12 matching lines @@
   // This is only used to set page-level focus in cross-process subframes, and
   // requests to set focus in main frame's SiteInstance are ignored.
   if (instance != root_manager->current_frame_host()->GetSiteInstance()) {
     RenderFrameProxyHost* proxy =
         root_manager->GetRenderFrameProxyHost(instance);
     proxy->Send(new InputMsg_SetFocus(proxy->GetRoutingID(), is_focused));
   }
 }
 
 }  // namespace content