AndroidOverlay implementation using Dialog.

content/browser/frame_host/render_frame_host_impl.cc

Index: content/browser/frame_host/render_frame_host_impl.cc
diff --git a/content/browser/frame_host/render_frame_host_impl.cc b/content/browser/frame_host/render_frame_host_impl.cc
index a3ca625f6be8be46a6a09a51b3efd5ff4d2094bb..97a5cd0c10a6342930069a16f7f4c8d87040c2c0 100644
--- a/content/browser/frame_host/render_frame_host_impl.cc
+++ b/content/browser/frame_host/render_frame_host_impl.cc
@@ -161,6 +161,15 @@ typedef base::hash_map<RenderFrameHostID, RenderFrameHostImpl*>
 base::LazyInstance<RoutingIDFrameMap>::DestructorAtExit g_routing_id_frame_map =
     LAZY_INSTANCE_INITIALIZER;
 
+#if defined(OS_ANDROID)
+typedef base::hash_map<base::UnguessableToken,
+                       RenderFrameHostImpl*,
+                       base::UnguessableTokenHash>
+    TokenFrameMap;
+base::LazyInstance<TokenFrameMap>::Leaky g_token_frame_map =
+    LAZY_INSTANCE_INITIALIZER;
+#endif
+
 // Translate a WebKit text direction into a base::i18n one.
 base::i18n::TextDirection WebTextDirectionToChromeTextDirection(
     blink::WebTextDirection dir) {
@@ -356,6 +365,16 @@ RenderFrameHostImpl* RenderFrameHostImpl::FromAXTreeID(
   return RenderFrameHostImpl::FromID(frame_id.first, frame_id.second);
 }
 
+#if defined(OS_ANDROID)
+// static
+RenderFrameHostImpl* RenderFrameHostImpl::FromOverlayRoutingToken(
+    const base::UnguessableToken& token) {
+  DCHECK_CURRENTLY_ON(BrowserThread::UI);
+  auto it = g_token_frame_map.Get().find(token);
+  return it == g_token_frame_map.Get().end() ? nullptr : it->second;
+}
+#endif
+
 RenderFrameHostImpl::RenderFrameHostImpl(SiteInstance* site_instance,
                                          RenderViewHostImpl* render_view_host,
                                          RenderFrameHostDelegate* delegate,
@@ -461,6 +480,10 @@ RenderFrameHostImpl::~RenderFrameHostImpl() {
   GetProcess()->RemoveRoute(routing_id_);
   g_routing_id_frame_map.Get().erase(
       RenderFrameHostID(GetProcess()->GetID(), routing_id_));
+#if defined(OS_ANDROID)
+  if (overlay_routing_token_.has_value())
+    g_token_frame_map.Get().erase(overlay_routing_token_.value());
+#endif
   BrowserThread::PostTask(BrowserThread::IO, FROM_HERE,
                           base::Bind(&NotifyRenderFrameDetachedOnIO,
                                      GetProcess()->GetID(), routing_id_));
@@ -514,6 +537,18 @@ ui::AXTreeIDRegistry::AXTreeID RenderFrameHostImpl::GetAXTreeID() {
       GetProcess()->GetID(), routing_id_);
 }
 
+#if defined(OS_ANDROID)
+const base::UnguessableToken& RenderFrameHostImpl::GetOverlayRoutingToken() {
+  if (!overlay_routing_token_.has_value()) {

[dcheng, 2017/04/06 07:14:51]

Slightly shorter to omit has_value()

[liberato (no reviews please), 2017/04/10 21:24:53]

Done.

+    overlay_routing_token_ = base::UnguessableToken::Create();
+    g_token_frame_map.Get().insert(

[dcheng, 2017/04/06 07:14:51]

Out of curiosity, does emplace work now?

[liberato (no reviews please), 2017/04/10 21:24:53]

yes, thanks.  done.

+        std::make_pair(overlay_routing_token_.value(), this));
+  }
+
+  return overlay_routing_token_.value();

[dcheng, 2017/04/06 07:14:51]

Shorter alternative: return *overlay_routing_token_.

(Similar comments for uses of Optional elsewhere)

[liberato (no reviews please), 2017/04/10 21:24:53]

Done, and elsewhere.

+}
+#endif
+
 SiteInstanceImpl* RenderFrameHostImpl::GetSiteInstance() {
   return site_instance_.get();
 }
@@ -821,6 +856,8 @@ bool RenderFrameHostImpl::OnMessageReceived(const IPC::Message &msg) {
 #if defined(OS_ANDROID)
     IPC_MESSAGE_HANDLER(FrameHostMsg_NavigationHandledByEmbedder,
                         OnNavigationHandledByEmbedder)
+    IPC_MESSAGE_HANDLER(FrameHostMsg_RequestOverlayRoutingToken,
+                        OnRequestOverlayRoutingToken)
 #endif
     IPC_MESSAGE_HANDLER(FrameHostMsg_ShowCreatedWindow, OnShowCreatedWindow)
   IPC_END_MESSAGE_MAP()
@@ -2434,6 +2471,14 @@ void RenderFrameHostImpl::OnNavigationHandledByEmbedder() {
 
   OnDidStopLoading();
 }
+
+void RenderFrameHostImpl::OnRequestOverlayRoutingToken() {
+  // Make sure that we have a token.
+  GetOverlayRoutingToken();
+
+  Send(new FrameMsg_SetOverlayRoutingToken(routing_id_,
+                                           overlay_routing_token_.value()));
+}
 #endif
 
 void RenderFrameHostImpl::OnShowCreatedWindow(int pending_widget_routing_id,