Change mojo enums to be scoped enums in the generated C++ bindings.

components/mus/public/interfaces/input_event_constants.mojom

Index: components/mus/public/interfaces/input_event_constants.mojom
diff --git a/components/mus/public/interfaces/input_event_constants.mojom b/components/mus/public/interfaces/input_event_constants.mojom
index 85cde70d44c4db2d84c196fe0c128827710f4712..03bd80bd342d8ba2d7ae5b57c426cd705ed5cacc 100644
--- a/components/mus/public/interfaces/input_event_constants.mojom
+++ b/components/mus/public/interfaces/input_event_constants.mojom
@@ -18,32 +18,28 @@ enum EventType {
 
 // This mirrors ui::EventFlags
 // TODO(morrita): Use shift operator once it is available.
-enum EventFlags {
-  NONE                 =      0,
-  IS_SYNTHESIZED       =      1,
-  SHIFT_DOWN           =      2,
-  CONTROL_DOWN         =      4,
-  ALT_DOWN             =      8,
-  COMMAND_DOWN         =     16,
-  ALTGR_DOWN           =     32,
-  MOD3_DOWN            =     64,
-  NUM_LOCK_ON          =    128,
-  CAPS_LOCK_ON         =    256,
-  SCROLL_LOCK_ON       =    512,
-  LEFT_MOUSE_BUTTON    =   1024,
-  MIDDLE_MOUSE_BUTTON  =   2048,
-  RIGHT_MOUSE_BUTTON   =   4096,
-  BACK_MOUSE_BUTTON    =   8192,
-  FORWARD_MOUSE_BUTTON =  16384,
-};
+const int32 kEventFlagNone               = 0x00000;
+const int32 kEventFlagIsSynthesized      = 0x00001;
+const int32 kEventFlagShiftDown          = 0x00002;
+const int32 kEventFlagControlDown        = 0x00004;
+const int32 kEventFlagAltDown            = 0x00008;
+const int32 kEventFlagCommandDown        = 0x00010;
+const int32 kEventFlagAltgrDown          = 0x00020;
+const int32 kEventFlagMod3Down           = 0x00040;
+const int32 kEventFlagNumLockOn          = 0x00080;
+const int32 kEventFlagCapsLockOn         = 0x00100;
+const int32 kEventFlagScrollLockOn       = 0x00200;
+const int32 kEventFlagLeftMouseButton    = 0x00400;
+const int32 kEventFlagMiddleMouseButton  = 0x00800;
+const int32 kEventFlagRightMouseButton   = 0x01000;
+const int32 kEventFlagBackMouseButton    = 0x02000;
+const int32 kEventFlagForwardMouseButton = 0x04000;
 
-enum MouseEventFlags {
-  IS_DOUBLE_CLICK      =  32768,
-  IS_TRIPLE_CLICK      =  65536,
-  IS_NON_CLIENT        = 131072,
+const int32 kMouseEventFlagIsDoubleClick = 0x08000;
+const int32 kMouseEventFlagIsTripleClick = 0x10000;
+const int32 kMouseEventFlagIsNonClient   = 0x20000;
 
-  // TODO(erg): Move accessibility flags and maybe synthetic touch events here.
-};
+// TODO(erg): Move accessibility flags and maybe synthetic touch events here.
 
 enum PointerKind {
   MOUSE,