Linux Aura: Use managed tab dragging when possible (Reland)

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 8cd8bde7a72b93b01e6e8e48ae0f3f53bb8302e0..eb61d9346750757cf4cae6f468fe8877218eab68 100644
--- a/ui/base/x/x11_util.h
+++ b/ui/base/x/x11_util.h
@@ -37,6 +37,22 @@ class SkBitmap;
 
 namespace ui {
 
+// These constants are defined in the EWMH spec for _NET_WM_MOVERESIZE.
+enum class NetWmMoveResize {
+  SIZE_TOPLEFT = 0,
+  SIZE_TOP = 1,
+  SIZE_TOPRIGHT = 2,
+  SIZE_RIGHT = 3,
+  SIZE_BOTTOMRIGHT = 4,
+  SIZE_BOTTOM = 5,
+  SIZE_BOTTOMLEFT = 6,
+  SIZE_LEFT = 7,
+  MOVE = 8,            // movement only
+  SIZE_KEYBOARD = 9,   // size via keyboard
+  MOVE_KEYBOARD = 10,  // move via keyboard
+  CANCEL = 11,         // cancel operation
+};
+
 // These functions use the default display and this /must/ be called from
 // the UI thread. Thus, they don't support multiple displays.
 
@@ -84,6 +100,13 @@ UI_BASE_X_EXPORT::Cursor CreateInvisibleCursor();
 // Sets whether |window| should use the OS window frame.
 UI_BASE_X_EXPORT void SetUseOSWindowFrame(XID window, bool use_os_window_frame);
 
+// Requests the window manager move or resize the window on behalf of Chromium.
+// Clients MUST release all grabs prior to calling.  Callers must check that the
+// WM supports the _NET_WM_MOVERESIZE protocol.
+UI_BASE_X_EXPORT void MoveResizeManagedWindow(XID window,
+                                              gfx::Point root_location,
+                                              NetWmMoveResize mode);
+
 // These functions do not cache their results --------------------------
 
 // Returns true if the shape extension is supported.