[Presentation API] Add support to content/ for multiple URLs per PresentationRequest.

content/renderer/presentation/presentation_dispatcher.cc

Index: content/renderer/presentation/presentation_dispatcher.cc
diff --git a/content/renderer/presentation/presentation_dispatcher.cc b/content/renderer/presentation/presentation_dispatcher.cc
index 293b030a88d9bfd911a4f29983d88b82e5d1d423..9f8f0bb887028e454aabd0ca5063fa2e9eb9f6e4 100644
--- a/content/renderer/presentation/presentation_dispatcher.cc
+++ b/content/renderer/presentation/presentation_dispatcher.cc
@@ -16,7 +16,7 @@
 #include "content/renderer/presentation/presentation_connection_client.h"
 #include "services/shell/public/cpp/interface_provider.h"
 #include "third_party/WebKit/public/platform/WebString.h"
-#include "third_party/WebKit/public/platform/WebURL.h"
+#include "third_party/WebKit/public/platform/WebVector.h"
 #include "third_party/WebKit/public/platform/modules/presentation/WebPresentationAvailabilityObserver.h"
 #include "third_party/WebKit/public/platform/modules/presentation/WebPresentationController.h"
 #include "third_party/WebKit/public/platform/modules/presentation/WebPresentationError.h"
@@ -100,37 +100,50 @@ void PresentationDispatcher::setController(
 }
 
 void PresentationDispatcher::startSession(
-    const blink::WebString& presentationUrl,
+    const blink::WebVector<blink::WebString>& presentationUrls,
     blink::WebPresentationConnectionClientCallbacks* callback) {
   DCHECK(callback);
   ConnectToPresentationServiceIfNeeded();
 
+  std::vector<url::mojom::UrlPtr> urls(presentationUrls.size());
+  std::transform(presentationUrls.begin(), presentationUrls.end(), urls.begin(),
+                 [](const blink::WebString& url) {
+                   url::mojom::UrlPtr mojo_url = url::mojom::Url::New();
+                   mojo_url->url = url.utf8();
+                   return mojo_url;
+                 });
+
   // The dispatcher owns the service so |this| will be valid when
   // OnSessionCreated() is called. |callback| needs to be alive and also needs
   // to be destroyed so we transfer its ownership to the mojo callback.
   presentation_service_->StartSession(
-      presentationUrl.utf8(),
+      std::move(urls),
       base::Bind(&PresentationDispatcher::OnSessionCreated,
-          base::Unretained(this),
-          base::Owned(callback)));
+                 base::Unretained(this), base::Owned(callback)));
 }
 
 void PresentationDispatcher::joinSession(
-    const blink::WebString& presentationUrl,
+    const blink::WebVector<blink::WebString>& presentationUrls,
     const blink::WebString& presentationId,
     blink::WebPresentationConnectionClientCallbacks* callback) {
   DCHECK(callback);
   ConnectToPresentationServiceIfNeeded();
 
+  std::vector<url::mojom::UrlPtr> urls(presentationUrls.size());
+  std::transform(presentationUrls.begin(), presentationUrls.end(), urls.begin(),
+                 [](const blink::WebString& url) {
+                   url::mojom::UrlPtr mojo_url = url::mojom::Url::New();
+                   mojo_url->url = url.utf8();
+                   return mojo_url;
+                 });
+
   // The dispatcher owns the service so |this| will be valid when
   // OnSessionCreated() is called. |callback| needs to be alive and also needs
   // to be destroyed so we transfer its ownership to the mojo callback.
   presentation_service_->JoinSession(
-      presentationUrl.utf8(),
-      presentationId.utf8(),
+      std::move(urls), presentationId.utf8(),
       base::Bind(&PresentationDispatcher::OnSessionCreated,
-          base::Unretained(this),
-          base::Owned(callback)));
+                 base::Unretained(this), base::Owned(callback)));
 }
 
 void PresentationDispatcher::sendString(
@@ -227,8 +240,10 @@ void PresentationDispatcher::closeSession(
     const blink::WebString& presentationId) {
   ConnectToPresentationServiceIfNeeded();
 
-  presentation_service_->CloseConnection(presentationUrl.utf8(),
-                                         presentationId.utf8());
+  url::mojom::UrlPtr url = url::mojom::Url::New();
+  url->url = presentationUrl.utf8();
+
+  presentation_service_->CloseConnection(std::move(url), presentationId.utf8());
 }
 
 void PresentationDispatcher::terminateSession(
@@ -236,8 +251,10 @@ void PresentationDispatcher::terminateSession(
     const blink::WebString& presentationId) {
   ConnectToPresentationServiceIfNeeded();
 
-  presentation_service_->Terminate(presentationUrl.utf8(),
-                                   presentationId.utf8());
+  url::mojom::UrlPtr url = url::mojom::Url::New();
+  url->url = presentationUrl.utf8();
+
+  presentation_service_->Terminate(std::move(url), presentationId.utf8());
 }
 
 void PresentationDispatcher::getAvailability(
@@ -290,10 +307,18 @@ void PresentationDispatcher::stopListening(
   UpdateListeningState(status_it->second.get());
 }
 
-void PresentationDispatcher::setDefaultPresentationUrl(
-    const blink::WebString& url) {
+void PresentationDispatcher::setDefaultPresentationUrls(
+    const blink::WebVector<blink::WebString>& presentationUrls) {
   ConnectToPresentationServiceIfNeeded();
-  presentation_service_->SetDefaultPresentationURL(url.utf8());
+
+  std::vector<url::mojom::UrlPtr> urls(presentationUrls.size());
+  std::transform(presentationUrls.begin(), presentationUrls.end(), urls.begin(),
+                 [](const blink::WebString& url) {
+                   url::mojom::UrlPtr mojo_url = url::mojom::Url::New();
+                   mojo_url->url = url.utf8();
+                   return mojo_url;
+                 });
+  presentation_service_->SetDefaultPresentationUrls(std::move(urls));
 }
 
 void PresentationDispatcher::DidCommitProvisionalLoad(
@@ -313,9 +338,9 @@ void PresentationDispatcher::OnDestruct() {
   delete this;
 }
 
-void PresentationDispatcher::OnScreenAvailabilityUpdated(const std::string& url,
+void PresentationDispatcher::OnScreenAvailabilityUpdated(url::mojom::UrlPtr url,
                                                          bool available) {
-  auto status_it = availability_status_.find(url);
+  auto status_it = availability_status_.find(url->url);
   if (status_it == availability_status_.end())
     return;
   AvailabilityStatus* status = status_it->second.get();
@@ -337,8 +362,8 @@ void PresentationDispatcher::OnScreenAvailabilityUpdated(const std::string& url,
 }
 
 void PresentationDispatcher::OnScreenAvailabilityNotSupported(
-    const std::string& url) {
-  auto status_it = availability_status_.find(url);
+    url::mojom::UrlPtr url) {
+  auto status_it = availability_status_.find(url->url);
   if (status_it == availability_status_.end())
     return;
   AvailabilityStatus* status = status_it->second.get();
@@ -426,7 +451,8 @@ void PresentationDispatcher::OnSessionMessagesReceived(
     // Note: Passing batches of messages to the Blink layer would be more
     // efficient.
     std::unique_ptr<PresentationConnectionClient> session_client(
-        new PresentationConnectionClient(session_info->url, session_info->id));
+        new PresentationConnectionClient(session_info->url->url,
+                                         session_info->id));
     switch (messages[i]->type) {
       case blink::mojom::PresentationMessageType::TEXT: {
         // TODO(mfoltz): Do we need to DCHECK(messages[i]->message)?
@@ -468,12 +494,14 @@ void PresentationDispatcher::UpdateListeningState(AvailabilityStatus* status) {
     return;
 
   ConnectToPresentationServiceIfNeeded();
+  url::mojom::UrlPtr url = url::mojom::Url::New();
+  url->url = status->url;
   if (should_listen) {
     status->listening_state = ListeningState::WAITING;
-    presentation_service_->ListenForScreenAvailability(status->url);
+    presentation_service_->ListenForScreenAvailability(std::move(url));
   } else {
     status->listening_state = ListeningState::INACTIVE;
-    presentation_service_->StopListeningForScreenAvailability(status->url);
+    presentation_service_->StopListeningForScreenAvailability(std::move(url));
   }
 }
 
@@ -492,7 +520,9 @@ PresentationDispatcher::CreateSendTextMessageRequest(
     const blink::WebString& message) {
   blink::mojom::PresentationSessionInfoPtr session_info =
       blink::mojom::PresentationSessionInfo::New();
-  session_info->url = presentationUrl.utf8();
+  url::mojom::UrlPtr url = url::mojom::Url::New();
+  url->url = presentationUrl.utf8();
+  session_info->url = std::move(url);
   session_info->id = presentationId.utf8();
 
   blink::mojom::SessionMessagePtr session_message =
@@ -513,7 +543,9 @@ PresentationDispatcher::CreateSendBinaryMessageRequest(
     size_t length) {
   blink::mojom::PresentationSessionInfoPtr session_info =
       blink::mojom::PresentationSessionInfo::New();
-  session_info->url = presentationUrl.utf8();
+  url::mojom::UrlPtr url = url::mojom::Url::New();

[dcheng, 2016/08/24 22:14:19]

What's the status on typemapping? We shouldn't have to manually marshall stuff
like this.

[mark a. foltz, 2016/08/24 22:37:11]

Sorry I don't understand the question.  The revised API takes a UrlPtr for
|session_info|.

[dcheng, 2016/08/24 23:12:17]

At this point, it's quite unusual to use the raw mojo types directly. It's much
nicer for code to just deal with some native Blink C++ struct. Then we use a
typemap + StructTraits to turn it into the mojo wire format, and then the same
thing on the other end to turn it back into a native C++ struct.

This is important, because the StructTraits actually have some checks: for
example, for GURL, it checks that the resulting GURL is actually valid and that
doesn't exceed max chars:
https://cs.chromium.org/chromium/src/url/mojo/url_gurl_struct_traits.h?rcl=0&...

It also results in simpler client code. For example, let's say we have:

interface PageLoadMetrics {
  void ReportLoaded(url.mojom.Url url);
};

Without typemapping, I'd have to write something like this:
  url::mojom::UrlPtr url = url::mojom::Url::New();
  url->url = gurl.possibly_invalid_spec();
  metrics->ReportLoaded(std::move(url));

But with typemapping, I can just write this:
  metrics->ReportLoaded(gurl);

FWIW, there's basically already a bug filed for this:
https://bugs.chromium.org/p/chromium/issues/detail?id=632623

[mark a. foltz, 2016/08/29 23:54:54]

Now passing GURL into all the Mojo interfaces.

+  url->url = presentationUrl.utf8();
+  session_info->url = std::move(url);
   session_info->id = presentationId.utf8();
 
   blink::mojom::SessionMessagePtr session_message =