Revert 237119 "Always create FrameTreeNodes and RenderFrameHosts..."

> Always create FrameTreeNodes and RenderFrameHosts for every frame.
> 
> This allows us to run the FrameTreeShape tests without a flag.
> 
> BUG=245126
> TEST=FrameTreeBrowserTest.FrameTreeShape*
> 
> Review URL: https://codereview.chromium.org/82033002

TBR=creis@chromium.org

Review URL: https://codereview.chromium.org/90213002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@237469 0039d316-1c4b-4281-b951-d872f2087c98

2 files changed, 43 insertions, 40 deletions

diff --git a/content/renderer/render_frame_impl.cc b/content/renderer/render_frame_impl.cc
index 6231d59..b2b7373 100644
--- a/content/renderer/render_frame_impl.cc
+++ b/content/renderer/render_frame_impl.cc
@@ -7,6 +7,7 @@
 #include <map>
 #include <string>
 
+#include "base/command_line.h"
 #include "base/strings/utf_string_conversions.h"
 #include "base/time/time.h"
 #include "content/child/appcache/appcache_dispatcher.h"
@@ -219,25 +220,27 @@ void RenderFrameImpl::didAccessInitialDocument(blink::WebFrame* frame) {
 blink::WebFrame* RenderFrameImpl::createChildFrame(
     blink::WebFrame* parent,
     const blink::WebString& name) {
+  RenderFrameImpl* child_render_frame = this;
   long long child_frame_identifier = WebFrame::generateEmbedderIdentifier();
-  // Synchronously notify the browser of a child frame creation to get the
-  // routing_id for the RenderFrame.
-  int routing_id = MSG_ROUTING_NONE;
-  Send(new FrameHostMsg_CreateChildFrame(GetRoutingID(),
-                                         parent->identifier(),
-                                         child_frame_identifier,
-                                         UTF16ToUTF8(name),
-                                         &routing_id));
-  if (routing_id == MSG_ROUTING_NONE)
-    return NULL;
-  RenderFrameImpl* child_render_frame = RenderFrameImpl::Create(render_view_,
-                                                                routing_id);
+  if (CommandLine::ForCurrentProcess()->HasSwitch(switches::kSitePerProcess)) {
+    // Synchronously notify the browser of a child frame creation to get the
+    // routing_id for the RenderFrame.
+    int routing_id;
+    Send(new FrameHostMsg_CreateChildFrame(GetRoutingID(),
+                                           parent->identifier(),
+                                           child_frame_identifier,
+                                           UTF16ToUTF8(name),
+                                           &routing_id));
+    child_render_frame = RenderFrameImpl::Create(render_view_, routing_id);
+  }
 
   blink::WebFrame* web_frame = WebFrame::create(child_render_frame,
                                                 child_frame_identifier);
 
-  g_child_frame_map.Get().insert(
-      std::make_pair(web_frame, child_render_frame));
+  if (CommandLine::ForCurrentProcess()->HasSwitch(switches::kSitePerProcess)) {
+    g_child_frame_map.Get().insert(
+        std::make_pair(web_frame, child_render_frame));
+  }
 
   return web_frame;
 }
@@ -252,41 +255,45 @@ void RenderFrameImpl::frameDetached(blink::WebFrame* frame) {
   // called on the parent frame.
   CHECK(!is_detaching_);
 
-  bool is_subframe = !!frame->parent();
   int64 parent_frame_id = -1;
-  if (is_subframe)
+  if (frame->parent())
     parent_frame_id = frame->parent()->identifier();
 
   Send(new FrameHostMsg_Detach(GetRoutingID(), parent_frame_id,
                                frame->identifier()));
 
-  // The |is_detaching_| flag disables Send(). FrameHostMsg_Detach must be
-  // sent before setting |is_detaching_| to true. In contrast, Observers
-  // should only be notified afterwards so they cannot call back into and
-  // have IPCs fired off.
-  is_detaching_ = true;
+  // Currently multiple WebCore::Frames can send frameDetached to a single
+  // RenderFrameImpl. This is legacy behavior from when RenderViewImpl served
+  // as a shared WebFrameClient for multiple Webcore::Frame objects. It also
+  // prevents this class from entering the |is_detaching_| state because
+  // even though one WebCore::Frame may have detached itself, others will
+  // still need to use this object.
+  if (CommandLine::ForCurrentProcess()->HasSwitch(switches::kSitePerProcess)) {
+    // The |is_detaching_| flag disables Send(). FrameHostMsg_Detach must be
+    // sent before setting |is_detaching_| to true. In contrast, Observers
+    // should only be notified afterwards so they cannot call back into and
+    // have IPCs fired off.
+    is_detaching_ = true;
+  }
 
   // Call back to RenderViewImpl for observers to be notified.
   // TODO(nasko): Remove once we have RenderFrameObserver.
   render_view_->frameDetached(frame);
 
-  // We need to clean up subframes by removing them from the map and deleting
-  // the RenderFrameImpl.  In contrast, the main frame is owned by its
-  // containing RenderViewHost (so that they have the same lifetime), so it does
-  // not require any cleanup here.
-  if (is_subframe) {
-    FrameMap::iterator it = g_child_frame_map.Get().find(frame);
-    DCHECK(it != g_child_frame_map.Get().end());
-    DCHECK_EQ(it->second, this);
-    g_child_frame_map.Get().erase(it);
-  }
-
-  // |frame| is invalid after here.
   frame->close();
 
-  if (is_subframe) {
-    delete this;
-    // Object is invalid after this point.
+  if (CommandLine::ForCurrentProcess()->HasSwitch(switches::kSitePerProcess)) {
+    // If the frame does not have a parent, it is the main frame. The main
+    // frame is owned by the containing RenderViewHost so it does not require
+    // any cleanup here.
+    if (frame->parent()) {
+      FrameMap::iterator it = g_child_frame_map.Get().find(frame);
+      DCHECK(it != g_child_frame_map.Get().end());
+      DCHECK_EQ(it->second, this);
+      g_child_frame_map.Get().erase(it);
+      delete this;
+      // Object is invalid after this point.
+    }
   }
 }
 
diff --git a/content/renderer/render_view_impl.cc b/content/renderer/render_view_impl.cc
index fe683d5..b21d9e0 100644
--- a/content/renderer/render_view_impl.cc
+++ b/content/renderer/render_view_impl.cc
@@ -3167,10 +3167,6 @@ void RenderViewImpl::didDisownOpener(blink::WebFrame* frame) {
 }
 
 void RenderViewImpl::frameDetached(WebFrame* frame) {
-  // NOTE: We may get here for either the main frame or for subframes.  The
-  // RenderFrameImpl will be deleted immediately after this call for subframes
-  // but not for the main frame, which is kept around in a scoped_ptr.
-
   FOR_EACH_OBSERVER(RenderViewObserver, observers_, FrameDetached(frame));
 }