mash: Don't synthesize extra key press events in the window server

ui/ozone/public/ozone_platform.h

Index: ui/ozone/public/ozone_platform.h
diff --git a/ui/ozone/public/ozone_platform.h b/ui/ozone/public/ozone_platform.h
index 97cab2cfebd51b060fd9870d7c7b618cebb65500..d30d8e6f627dee69b05179a0a02e1cdc5c7abcd9 100644
--- a/ui/ozone/public/ozone_platform.h
+++ b/ui/ozone/public/ozone_platform.h
@@ -7,6 +7,7 @@
 
 #include <memory>
 
+#include "base/auto_reset.h"
 #include "base/macros.h"
 #include "base/message_loop/message_loop.h"
 #include "ui/ozone/ozone_export.h"
@@ -126,6 +127,8 @@ class OZONE_EXPORT OzonePlatform {
   virtual void AddInterfaces(service_manager::InterfaceRegistry* registry);
 
  private:
+  friend class ScopedOzonePlatformForTesting;
+
   virtual void InitializeUI(const InitParams& params) = 0;
   virtual void InitializeGPU(const InitParams& params) = 0;
 
@@ -134,6 +137,18 @@ class OZONE_EXPORT OzonePlatform {
   DISALLOW_COPY_AND_ASSIGN(OzonePlatform);
 };
 
+// Allows the ozone platform instance to be overridden in tests.
+class OZONE_EXPORT ScopedOzonePlatformForTesting {
+ public:
+  ScopedOzonePlatformForTesting(OzonePlatform* test_instance);
+  ~ScopedOzonePlatformForTesting();
+
+ private:
+  base::AutoReset<OzonePlatform*> auto_reset_;
+
+  DISALLOW_COPY_AND_ASSIGN(ScopedOzonePlatformForTesting);
+};
+
 }  // namespace ui
 
 #endif  // UI_OZONE_PUBLIC_OZONE_PLATFORM_H_