Don't use Skia internal src file GrGLDefines. (#32491)

Skia's src files are not stable and may change constantly, flutter should not ever including them.
diff --git a/testing/test_gl_surface.cc b/testing/test_gl_surface.cc
index 885b852..8c240b3 100644
--- a/testing/test_gl_surface.cc
+++ b/testing/test_gl_surface.cc
@@ -16,7 +16,6 @@
 #include "third_party/skia/include/core/SkColorType.h"
 #include "third_party/skia/include/core/SkSurface.h"
 #include "third_party/skia/include/gpu/gl/GrGLAssembleInterface.h"
-#include "third_party/skia/src/gpu/gl/GrGLDefines.h"
 
 namespace flutter {
 namespace testing {
@@ -301,9 +300,9 @@
   const uint32_t height = surface_size_.height();
   framebuffer_info.fFBOID = GetFramebuffer(width, height);
 #if FML_OS_MACOSX
-  framebuffer_info.fFormat = GR_GL_RGBA8;
+  framebuffer_info.fFormat = 0x8058;  // GL_RGBA8
 #else
-  framebuffer_info.fFormat = GR_GL_BGRA8;
+  framebuffer_info.fFormat = 0x93A1;  // GL_BGRA8;
 #endif
 
   GrBackendRenderTarget backend_render_target(