Move ownership of PowerSaveBlocker from WakeLockServiceContext to WakeLockServiceImpl

content/public/browser/web_contents.h

Index: content/public/browser/web_contents.h
diff --git a/content/public/browser/web_contents.h b/content/public/browser/web_contents.h
index 2d788807cbf73cab3dab325e127db1e55237678e..ebd18a09057faf726baa082d4d1e9d41860173ee 100644
--- a/content/public/browser/web_contents.h
+++ b/content/public/browser/web_contents.h
@@ -44,6 +44,12 @@ namespace blink {
 struct WebFindOptions;
 }
 
+namespace device {
+namespace mojom {
+class WakeLockContext;
+}
+}
+
 namespace net {
 struct LoadStateWithParam;
 }
@@ -674,6 +680,9 @@ class WebContents : public PageNavigator,
   // otherwise.
   virtual WebContents* GetOriginalOpener() const = 0;
 
+  // Returns the WakeLockContext accociated with this WebContents.
+  virtual device::mojom::WakeLockContext* GetWakeLockContext() = 0;
+
   typedef base::Callback<void(
       int, /* id */
       int, /* HTTP status code */