Use WeakInterfacePtr for Geolocation

Make Geolocation use WeakInterfacePtr, which is the class to use
so that mojo interface handles do not need to be manually closed
on Execution context destruction.

WeakInterfacePtr are the new hotness, they do that automatically
on Execution context destruction.

No new tests, no change in behavior, covered by existing tests.

Bug: 800641
Change-Id: Icf5347c012c735b03676d2537cae4473f03fc568
Reviewed-on: https://chromium-review.googlesource.com/880246
Commit-Queue: Austin Tankiang <austinct@google.com>
Reviewed-by: Kentaro Hara <haraken@chromium.org>
Reviewed-by: Noel Gordon <noel@chromium.org>
Reviewed-by: Sam McNally <sammc@chromium.org>
Cr-Commit-Position: refs/heads/master@{#532795}

third_party/WebKit/Source/modules/geolocation/Geolocation.cpp

@@ -140,7 +140,6 @@ LocalFrame* Geolocation::GetFrame() const {
 }
 
 void Geolocation::ContextDestroyed(ExecutionContext*) {
-  geolocation_service_.reset();
   CancelAllRequests();
   StopUpdating();
   last_position_ = nullptr;
@@ -484,10 +483,12 @@ void Geolocation::UpdateGeolocationConnection() {
   if (geolocation_)
     return;
 
+  InterfaceInvalidator* invalidator =
+      GetExecutionContext()->GetInterfaceInvalidator();
   GetFrame()->GetInterfaceProvider().GetInterface(
-      mojo::MakeRequest(&geolocation_service_));
+      MakeRequest(&geolocation_service_, invalidator));
   geolocation_service_->CreateGeolocation(
-      mojo::MakeRequest(&geolocation_),
+      MakeRequest(&geolocation_, invalidator),
       Frame::HasTransientUserActivation(GetFrame()));
 
   geolocation_.set_connection_error_handler(WTF::Bind(

third_party/WebKit/Source/modules/geolocation/Geolocation.h

@@ -190,8 +190,8 @@ class MODULES_EXPORT Geolocation final
   GeolocationWatchers watchers_being_invoked_;
   Member<Geoposition> last_position_;
 
-  device::mojom::blink::GeolocationPtr geolocation_;
-  mojom::blink::GeolocationServicePtr geolocation_service_;
+  device::mojom::blink::WeakGeolocationPtr geolocation_;
+  mojom::blink::WeakGeolocationServicePtr geolocation_service_;
   bool enable_high_accuracy_ = false;
 
   // Whether a GeoNotifier is waiting for a position update.