Fixes for building with --disable-gl

This fixes a few problems that occur when only using a GLES2 header.

• The use of GL_CLAMP_TO_BORDER and GL_MIRRORED_REPEAT were moved from
  cogl-pipelinelayer-state.h to cogl-sampler-cache-private.h but the
  corresponding defines were not.

• cogl-sampler-cache.c was using GL_TEXTURE_WRAP_R but this is only
  defined as GL_TEXTURE_WRAP_R_OES from the GLES2 header so it needs a
  #define.

• cogl-framebuffer-private.h uses GLuint but it does not include
  cogl-gl-header.h. It gets away with this when GLX support is enabled
  because the GL header would be included via glx.h.

Reviewed-by: Robert Bragg <robert@linux.intel.com>

(cherry picked from commit 9cdb87c864fc262c4b26c13963670d60d7c18058)

cogl/cogl-framebuffer-private.h

@@ -31,6 +31,7 @@
 #include "cogl-winsys-private.h"
 #include "cogl-attribute-private.h"
 #include "cogl-offscreen.h"
+#include "cogl-gl-header.h"
 
 #ifdef COGL_HAS_XLIB_SUPPORT
 #include <X11/Xlib.h>

cogl/cogl-pipeline-layer-private.h

@@ -39,14 +39,6 @@
 
 #include <glib.h>
 
-/* This isn't defined in the GLES headers */
-#ifndef GL_CLAMP_TO_BORDER
-#define GL_CLAMP_TO_BORDER 0x812d
-#endif
-#ifndef GL_MIRRORED_REPEAT
-#define GL_MIRRORED_REPEAT 0x8370
-#endif
-
 typedef struct _CoglPipelineLayer     CoglPipelineLayer;
 #define COGL_PIPELINE_LAYER(OBJECT) ((CoglPipelineLayer *)OBJECT)
 

cogl/cogl-sampler-cache-private.h

@@ -28,6 +28,14 @@
 #include "cogl-context.h"
 #include "cogl-gl-header.h"
 
+/* These aren't defined in the GLES headers */
+#ifndef GL_CLAMP_TO_BORDER
+#define GL_CLAMP_TO_BORDER 0x812d
+#endif
+#ifndef GL_MIRRORED_REPEAT
+#define GL_MIRRORED_REPEAT 0x8370
+#endif
+
 /* GL_ALWAYS is just used here as a value that is known not to clash
  * with any valid GL wrap modes.
  *

cogl/cogl-sampler-cache.c

@@ -31,6 +31,10 @@
 #include "cogl-sampler-cache-private.h"
 #include "cogl-context-private.h"
 
+#ifndef GL_TEXTURE_WRAP_R
+#define GL_TEXTURE_WRAP_R 0x8072
+#endif
+
 struct _CoglSamplerCache
 {
   CoglContext *context;