Add the xrender backend to the window manager.

compositor/texture_data.h

Index: compositor/texture_data.h
diff --git a/compositor/texture_data.h b/compositor/texture_data.h
index 56f50b8c49c141942363b275471ace96ec689bcb..824ef291b0e41b5056bd9564e0288f994f97596d 100644
--- a/compositor/texture_data.h
+++ b/compositor/texture_data.h
@@ -5,12 +5,14 @@
 #ifndef WINDOW_MANAGER_COMPOSITOR_TEXTURE_DATA_H_
 #define WINDOW_MANAGER_COMPOSITOR_TEXTURE_DATA_H_
 
+#include <stdint.h>
+
 namespace window_manager {
 
 class TextureData {
  public:
   virtual ~TextureData() {}
-  GLuint texture() const { return texture_; }
+  uint32_t texture() const { return texture_; }
 
   bool has_alpha() const { return has_alpha_; }
   void set_has_alpha(bool has_alpha) { has_alpha_ = has_alpha; }
@@ -19,11 +21,11 @@ class TextureData {
  protected:
   // TextureData is not allowed to be instantiated.
   TextureData() : texture_(0), has_alpha_(true) {}
-  void set_texture(GLuint texture) { texture_ = texture; }
-  const GLuint* texture_ptr() { return &texture_; }
+  void set_texture(uint32_t texture) { texture_ = texture; }
+  const uint32_t* texture_ptr() { return &texture_; }
 
  private:
-  GLuint texture_;
+  uint32_t texture_;
   bool has_alpha_;
   DISALLOW_COPY_AND_ASSIGN(TextureData);
 };