aura-x11: Add custom web cursor support.

ui/base/x/x11_util.h

Index: ui/base/x/x11_util.h
diff --git a/ui/base/x/x11_util.h b/ui/base/x/x11_util.h
index 86955bf5d3e783ab89812b8f4f50b660aadadd0d..25f5b205c7721fc686713d6bd8a217a864a17fcb 100644
--- a/ui/base/x/x11_util.h
+++ b/ui/base/x/x11_util.h
@@ -24,6 +24,7 @@ typedef unsigned long XID;
 typedef unsigned long XSharedMemoryId;  // ShmSeg in the X headers.
 typedef struct _XDisplay Display;
 typedef unsigned long Cursor;
+typedef struct _XcursorImage XcursorImage;
 
 #if defined(TOOLKIT_USES_GTK)
 typedef struct _GdkDrawable GdkWindow;
@@ -77,6 +78,19 @@ const int kCursorClearXCursorCache = -1;
 // |cursor_shape| is an X font cursor shape, see XCreateFontCursor().
 UI_EXPORT Cursor GetXCursor(int cursor_shape);
 
+#if defined(USE_AURA)
+// Creates a custom X cursor from the image. This takes ownership of image. The
+// caller must not free/modify the image. The refcount of the newly created
+// cursor is set to 1.
+UI_EXPORT Cursor CreateReffedCustomXCursor(XcursorImage* image);
+
+// Increases the refcount of the custom cursor.
+UI_EXPORT void RefCustomXCursor(Cursor cursor);
+
+// Decreases the refcount of the custom cursor, and destroys it if it reaches 0.
+UI_EXPORT void UnrefCustomXCursor(Cursor cursor);
+#endif
+
 // These functions do not cache their results --------------------------
 
 // Get the X window id for the default root window