Declarative resource hints go through mojo IPC to //content

third_party/WebKit/Source/platform/network/NetworkHints.cpp

Index: third_party/WebKit/Source/platform/network/NetworkHints.cpp
diff --git a/third_party/WebKit/Source/platform/network/NetworkHints.cpp b/third_party/WebKit/Source/platform/network/NetworkHints.cpp
index c2c99f7c232bf9945552c288d0cd6cb31acfedc8..f780329c63b9c5b859466000510ef3e61eddc5c9 100644
--- a/third_party/WebKit/Source/platform/network/NetworkHints.cpp
+++ b/third_party/WebKit/Source/platform/network/NetworkHints.cpp
@@ -27,11 +27,12 @@
 #include "platform/network/NetworkHints.h"
 
 #include "public/platform/Platform.h"
+#include "public/platform/ServiceRegistry.h"
 #include "public/platform/WebPrescientNetworking.h"
 
 namespace blink {
 
-void prefetchDNS(const String& hostname)
+void speculativePrefetchDNS(const String& hostname)
 {
     if (WebPrescientNetworking* prescientNetworking = Platform::current()->prescientNetworking())
         prescientNetworking->prefetchDNS(hostname);
@@ -39,10 +40,36 @@ void prefetchDNS(const String& hostname)
 
 void preconnect(const KURL& url, const CrossOriginAttributeValue crossOrigin)
 {
-    if (WebPrescientNetworking* prescientNetworking = Platform::current()->prescientNetworking()) {
-        bool allowCredentials = (crossOrigin != CrossOriginAttributeAnonymous);
-        prescientNetworking->preconnect(url, allowCredentials);
-    }
+    ResourceHintsDispatcher::instance().preconnect(url, crossOrigin, 1);
+}
+
+void prefetchDNS(const KURL& url)
+{
+    ResourceHintsDispatcher::instance().preresolve(url);
+}
+
+// static
+ResourceHintsDispatcher& ResourceHintsDispatcher::instance()
+{
+    DEFINE_STATIC_LOCAL(ResourceHintsDispatcher, dispatcher, ());

[kinuko, 2016/06/09 07:09:19]

For platform-level mojo calls I'm still not fully sure if we should just keep
adding these as static (I imagine we'll have more)... I think we could possibly
think about gathering these in a single place, e.g. within Platform.

[Charlie Harrison, 2016/06/10 14:20:00]

Good idea. This will make testing simpler too (I think we can use MockPlatform
instead of mocking NetworkHintsInterface).

+    return dispatcher;
+}
+
+void ResourceHintsDispatcher::preconnect(const KURL& url, CrossOriginAttributeValue crossOrigin, int numConnections)
+{
+    bool credentialsFlag = (crossOrigin != CrossOriginAttributeAnonymous);
+    m_host->DispatchPreconnect(url, credentialsFlag, numConnections);
+}
+
+void ResourceHintsDispatcher::preresolve(const KURL& url)
+{
+    m_host->DispatchPreresolve(url);
+}
+
+ResourceHintsDispatcher::ResourceHintsDispatcher()
+{
+    DCHECK(!m_host.is_bound());

[yzshen1, 2016/06/08 17:40:53]

nit: this DCHECK is not very useful because default constructed InterfacePtr is
always not bound.

[Charlie Harrison, 2016/06/10 14:20:00]

Done.

+    Platform::current()->serviceRegistry()->connectToRemoteService(mojo::GetProxy(&m_host));
 }
 
 } // namespace blink