aura-x11: Add custom web cursor support.

ui/aura/root_window_host_linux.cc

Index: ui/aura/root_window_host_linux.cc
diff --git a/ui/aura/root_window_host_linux.cc b/ui/aura/root_window_host_linux.cc
index 57f6394bfef26de22d21c9eb358a00656ce8303b..e4622b696641b00182716b03796686eaf60681f5 100644
--- a/ui/aura/root_window_host_linux.cc
+++ b/ui/aura/root_window_host_linux.cc
@@ -152,9 +152,11 @@ int CursorShapeFromNative(gfx::NativeCursor native_cursor) {
     case aura::kCursorZoomOut:
     case aura::kCursorGrab:
     case aura::kCursorGrabbing:
-    case aura::kCursorCustom:
       // TODO(jamescook): Need cursors for these.  crbug.com/111650
       return XC_left_ptr;
+    case aura::kCursorCustom:
+      NOTREACHED();
+      return XC_left_ptr;
   }
   NOTREACHED();
   return XC_left_ptr;
@@ -273,6 +275,7 @@ RootWindowHostLinux::RootWindowHostLinux(const gfx::Rect& bounds)
       xwindow_(0),
       x_root_window_(DefaultRootWindow(xdisplay_)),
       current_cursor_(aura::kCursorNull),
+      custom_cursor_(0),
       cursor_shown_(true),
       bounds_(bounds) {
   XSetWindowAttributes swa;
@@ -317,6 +320,11 @@ RootWindowHostLinux::RootWindowHostLinux(const gfx::Rect& bounds)
 }
 
 RootWindowHostLinux::~RootWindowHostLinux() {
+  if (custom_cursor_) {
+    ui::UnrefCustomXCursor(custom_cursor_);
+    custom_cursor_ = 0;
+  }
+
   XDestroyWindow(xdisplay_, xwindow_);
 
   // Clears XCursorCache.
@@ -542,14 +550,26 @@ void RootWindowHostLinux::SetCursor(gfx::NativeCursor cursor) {
     return;
   current_cursor_ = cursor;
 
-  // Custom web cursors are handled directly.
-  if (cursor == kCursorCustom)
-    return;
+  if (custom_cursor_) {
+    ui::UnrefCustomXCursor(custom_cursor_);
+    custom_cursor_ = 0;
+  }
 
   if (cursor_shown_)
     SetCursorInternal(cursor);
 }
 
+void RootWindowHostLinux::SetCustomCursor(const gfx::PlatformCursor& cursor) {
+  if (custom_cursor_)
+    ui::UnrefCustomXCursor(custom_cursor_);
+  custom_cursor_ = cursor;
+  if (custom_cursor_)

[Daniel Erat, 2012/02/24 23:19:31]

should this method CHECK(cursor)?  i'm pretty sure that passing 0 will generate
a BadCursor error

[sadrul, 2012/02/25 00:02:30]

I just removed the if check here. The XCustomCursorCache code will crash for a 0
(or any unknown cursor).

+    ui::RefCustomXCursor(custom_cursor_);
+  current_cursor_ = kCursorCustom;
+  if (cursor_shown_)
+    SetCursorInternal(current_cursor_);
+}
+
 void RootWindowHostLinux::ShowCursor(bool show) {
   if (show == cursor_shown_)
     return;
@@ -645,6 +665,8 @@ void RootWindowHostLinux::SetCursorInternal(gfx::NativeCursor cursor) {
   ::Cursor xcursor =
       cursor == kCursorNone ?
       invisible_cursor_ :
+      cursor == kCursorCustom ?
+      custom_cursor_ :
       ui::GetXCursor(CursorShapeFromNative(cursor));
   XDefineCursor(xdisplay_, xwindow_, xcursor);
 }