Convert app banners to use Mojo.

third_party/WebKit/Source/web/WebLocalFrameImpl.cpp

 /*
  * Copyright (C) 2009 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 159 matching lines @@
 #include "platform/graphics/skia/SkiaUtils.h"
 #include "platform/heap/Handle.h"
 #include "platform/network/ResourceRequest.h"
 #include "platform/scroll/ScrollTypes.h"
 #include "platform/scroll/ScrollbarTheme.h"
 #include "platform/tracing/TraceEvent.h"
 #include "platform/weborigin/KURL.h"
 #include "platform/weborigin/SchemeRegistry.h"
 #include "platform/weborigin/SecurityPolicy.h"
 #include "public/platform/InterfaceProvider.h"
+#include "public/platform/InterfaceRegistry.h"
 #include "public/platform/WebDoubleSize.h"
 #include "public/platform/WebFloatPoint.h"
 #include "public/platform/WebFloatRect.h"
 #include "public/platform/WebLayer.h"
 #include "public/platform/WebPoint.h"
 #include "public/platform/WebRect.h"
 #include "public/platform/WebSecurityOrigin.h"
 #include "public/platform/WebSize.h"
 #include "public/platform/WebSuspendableTask.h"
 #include "public/platform/WebURLError.h"
@@ skipping 31 matching lines @@
 #include "web/WebDevToolsAgentImpl.h"
 #include "web/WebFrameWidgetImpl.h"
 #include "web/WebPluginContainerImpl.h"
 #include "web/WebRemoteFrameImpl.h"
 #include "web/WebViewImpl.h"
 #include "wtf/CurrentTime.h"
 #include "wtf/HashMap.h"
 #include "wtf/PtrUtil.h"
 #include <algorithm>
 #include <memory>
+#include <utility>
 
 namespace blink {
 
 static int frameCount = 0;
 
 static HeapVector<ScriptSourceCode> createSourcesVector(
     const WebScriptSource* sourcesIn,
     unsigned numSources) {
   HeapVector<ScriptSourceCode> sources;
   sources.append(sourcesIn, numSources);
@@ skipping 1366 matching lines @@
                                             const AtomicString& uniqueName) {
   setCoreFrame(
       LocalFrame::create(m_frameLoaderClientImpl.get(), host, owner,
                          client() ? client()->interfaceProvider() : nullptr,
                          client() ? client()->interfaceRegistry() : nullptr));
   frame()->tree().setPrecalculatedName(name, uniqueName);
   // We must call init() after m_frame is assigned because it is referenced
   // during init(). Note that this may dispatch JS events; the frame may be
   // detached after init() returns.
   frame()->init();
-  if (frame() &&
-      frame()->loader().stateMachine()->isDisplayingInitialEmptyDocument() &&
-      !parent() && !opener() &&
-      frame()->settings()->shouldReuseGlobalForUnownedMainFrame())
-    frame()->document()->getSecurityOrigin()->grantUniversalAccess();
+  if (frame()) {
+    if (frame()->loader().stateMachine()->isDisplayingInitialEmptyDocument() &&
+        !parent() && !opener() &&
+        frame()->settings()->shouldReuseGlobalForUnownedMainFrame()) {
+      frame()->document()->getSecurityOrigin()->grantUniversalAccess();
+    }
+
+    frame()->interfaceRegistry()->addInterface(
+        WTF::bind(&AppBannerController::create, wrapPersistent(frame())));

[haraken, 2016/10/20 15:51:23]

I'm just curious but why does addInterface take a WTF::Function instead of the
created InterfacePtr?

[dominickn, 2016/10/20 23:41:18]

addInterface registers a WTF::Function(request) callback to be run when it
receives a request of the type expected by the callback. When you call
addInterface, you don't have an InterfaceRequest (InterfacePtr is the "other
end" of the Mojo pipe; when you register an interface the callback expects an
InterfaceRequest). All you're doing in addInterface is saying, "run this
callback when you receive that type of request".

AppBannerController::create is bound with the frame and expects one additional
argument, which is a mojo::InterfaceRequest<AppBannerClient>. When that request
comes in (via the AppBannerManager calling SendBannerPromptRequest), the
WTF::Function is invoked to lazily create an AppBannerController, passing in the
InterfaceRequest.

[haraken, 2016/10/21 08:59:45]

Sorry for being noisy, but where is the expected request type specified?
addInterface just takes a WTF::Function and it doesn't know when to invoke the
function.

[dominickn, 2016/10/21 12:26:57]

The short answer is template magic. :)

The long answer is that the WTF::Function must have an
InterfaceRequest<Interface> parameter in its signature (see
AppBannerController:bindMojoRequest). The Interface template class is the
generated mojo interface class, which is blink::mojom::AppBannerController in
this case. Mojo always injects a static, unique Name_ member into the generated
classes; addInterface simply maps blink::mojom::AppBannerController::Name_ to
the WTF::Function which is passed in.

So now we query the interface registry. That passes in an
InterfaceRequest<blink::mojom::AppBannerController>, so the registry just looks
up whether there is a WTF::Function mapped to
blink::mojom::AppBannerController::Name_, and runs it passing the request. This
creates a concrete AppBannerController and binds the pipe, allowing the other
end of the pipe to call methods on the AppBannerController. This is mostly
implemented inside the services / mojo layer and is pretty much all
automatically generated. Does that make sense?

If you're interested, the actual impl is
https://cs.chromium.org/chromium/src/services/service_manager/public/cpp/inte...
and
https://cs.chromium.org/chromium/src/services/service_manager/public/cpp/lib/...

[haraken, 2016/10/23 22:42:15]

Thanks, makes sense.

I'd personally prefer a more explicit binding API but delegate the decision to
Mojo experts :)

+  }
 }
 
 LocalFrame* WebLocalFrameImpl::createChildFrame(
     const FrameLoadRequest& request,
     const AtomicString& name,
     HTMLFrameOwnerElement* ownerElement) {
   DCHECK(m_client);
   TRACE_EVENT0("blink", "WebLocalFrameImpl::createChildframe");
   WebTreeScopeType scope = frame()->document() == ownerElement->treeScope()
                                ? WebTreeScopeType::Document
@@ skipping 450 matching lines @@
 
   // Screen Orientation API
   if (ScreenOrientationController::from(*frame()))
     ScreenOrientationController::from(*frame())->notifyOrientationChanged();
 
   // Legacy window.orientation API
   if (RuntimeEnabledFeatures::orientationEventEnabled() && frame()->domWindow())
     frame()->localDOMWindow()->sendOrientationChangeEvent();
 }
 
-void WebLocalFrameImpl::willShowInstallBannerPrompt(
-    int requestId,
-    const WebVector<WebString>& platforms,
-    WebAppBannerPromptReply* reply) {
-  if (!frame())
-    return;
-
-  AppBannerController::willShowInstallBannerPrompt(
-      requestId, client()->appBannerClient(), frame(), platforms, reply);
-}
-
 void WebLocalFrameImpl::requestRunTask(WebSuspendableTask* task) const {
   DCHECK(frame());
   DCHECK(frame()->document());
   frame()->document()->postSuspendableTask(
       WebSuspendableTaskWrapper::create(wrapUnique(task)));
 }
 
 void WebLocalFrameImpl::didCallAddSearchProvider() {
   UseCounter::count(frame(), UseCounter::ExternalAddSearchProvider);
 }
@@ skipping 266 matching lines @@
     feature = UseCounter::ChromeLoadTimesNpnNegotiatedProtocol;
   } else if (metric == "wasAlternateProtocolAvailable") {
     feature = UseCounter::ChromeLoadTimesWasAlternateProtocolAvailable;
   } else if (metric == "connectionInfo") {
     feature = UseCounter::ChromeLoadTimesConnectionInfo;
   }
   UseCounter::count(frame(), feature);
 }
 
 }  // namespace blink