html_viewer: Move webcrypto to a place where html_viewer can use it.

mojo/services/html_viewer/blink_platform_impl.h

Index: mojo/services/html_viewer/blink_platform_impl.h
diff --git a/mojo/services/html_viewer/blink_platform_impl.h b/mojo/services/html_viewer/blink_platform_impl.h
index 17cca38942d4161b02f4269f23281401dc31275e..c6d9844d045c51d6b8c64dc578e46934cf79929a 100644
--- a/mojo/services/html_viewer/blink_platform_impl.h
+++ b/mojo/services/html_viewer/blink_platform_impl.h
@@ -10,6 +10,7 @@
 #include "base/threading/thread_local_storage.h"
 #include "base/timer/timer.h"
 #include "cc/blink/web_compositor_support_impl.h"
+#include "components/webcrypto/webcrypto_impl.h"
 #include "mojo/services/html_viewer/blink_resource_map.h"
 #include "mojo/services/html_viewer/webmimeregistry_impl.h"
 #include "mojo/services/html_viewer/webscheduler_impl.h"
@@ -61,6 +62,7 @@ class BlinkPlatformImpl : public blink::Platform {
       blink::WebGestureDevice device_source,
       const blink::WebFloatPoint& velocity,
       const blink::WebSize& cumulative_scroll) override;
+  blink::WebCrypto* crypto() override;
 
  private:
   void SuspendSharedTimer();
@@ -84,6 +86,7 @@ class BlinkPlatformImpl : public blink::Platform {
   WebThemeEngineImpl theme_engine_;
   WebMimeRegistryImpl mime_registry_;
   WebSchedulerImpl scheduler_;
+  components::webcrypto::WebCryptoImpl web_crypto_;
   blink::WebScrollbarBehavior scrollbar_behavior_;
   BlinkResourceMap blink_resource_map_;