Forward-declare blink::mojom::EngagementLevel

third_party/WebKit/Source/core/dom/Document.h

Index: third_party/WebKit/Source/core/dom/Document.h
diff --git a/third_party/WebKit/Source/core/dom/Document.h b/third_party/WebKit/Source/core/dom/Document.h
index cef1413cc304fe07171fba0db17eeea9d28a7c6d..76f2c1ae609b4a8e2bfcfcaaf71c5d6d371c78e4 100644
--- a/third_party/WebKit/Source/core/dom/Document.h
+++ b/third_party/WebKit/Source/core/dom/Document.h
@@ -63,7 +63,6 @@
 #include "platform/weborigin/ReferrerPolicy.h"
 #include "public/platform/WebFocusType.h"
 #include "public/platform/WebInsecureRequestPolicy.h"
-#include "public/platform/site_engagement.mojom-blink.h"
 #include "wtf/Compiler.h"
 #include "wtf/HashSet.h"
 #include "wtf/PassRefPtr.h"
@@ -71,6 +70,10 @@
 
 namespace blink {
 
+namespace mojom {
+enum class EngagementLevel;

[tapted, 2017/02/06 03:29:23]

This is implicitly `int` -- see "(3)" at
http://en.cppreference.com/w/cpp/language/enum#Scoped_enumerations -- but the
mojo header declares it as int32_t

They're "probably" the same size on the platforms Chrome supports, but I think
this should be 

enum class EngagementLevel : int32_t;

anyway, I'm the current chromium sheriff, and this has become Pri-0. This CL
needs a rebase and fails presubmits now that clang-format sorts headers for you,
so I've made https://codereview.chromium.org/2677003002/ and referenced the CL
here.

+}
+
 class AnimationClock;
 class DocumentTimeline;
 class AXObjectCache;
@@ -1201,10 +1204,10 @@ class CORE_EXPORT Document : public ContainerNode,
   Document& ensureTemplateDocument();
   Document* templateDocumentHost() { return m_templateDocumentHost; }
 
-  mojom::blink::EngagementLevel getEngagementLevel() const {
+  mojom::EngagementLevel getEngagementLevel() const {
     return m_engagementLevel;
   }
-  void setEngagementLevel(mojom::blink::EngagementLevel level) {
+  void setEngagementLevel(mojom::EngagementLevel level) {
     m_engagementLevel = level;
   }