Move SkGLContext and some GrGLInterface implementations to skgputest module

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1815823002
CQ_EXTRA_TRYBOTS=client.skia.compile:Build-Ubuntu-GCC-x86_64-Release-CMake-Trybot,Build-Mac-Clang-x86_64-Release-CMake-Trybot

Committed: https://skia.googlesource.com/skia/+/fe3456cb006110d045b26ff3f8681b893a757b58

Review URL: https://codereview.chromium.org/1815823002
diff --git a/samplecode/SampleApp.cpp b/samplecode/SampleApp.cpp
index e0d152d..780eabd 100644
--- a/samplecode/SampleApp.cpp
+++ b/samplecode/SampleApp.cpp
@@ -33,11 +33,14 @@
 #include "sk_tool_utils.h"
 
 #if SK_SUPPORT_GPU
-#include "gl/GrGLInterface.h"
-#include "gl/GrGLUtil.h"
-#include "GrRenderTarget.h"
-#include "GrContext.h"
-#include "SkGpuDevice.h"
+#   include "gl/GrGLInterface.h"
+#   include "gl/GrGLUtil.h"
+#   include "GrRenderTarget.h"
+#   include "GrContext.h"
+#   include "SkGpuDevice.h"
+#   if SK_ANGLE
+#       include "gl/angle/GLContext_angle.h"
+#   endif
 #else
 class GrContext;
 #endif
@@ -233,7 +236,7 @@
                 break;
 #if SK_ANGLE
             case kANGLE_DeviceType:
-                glInterface.reset(GrGLCreateANGLEInterface());
+                glInterface.reset(sk_gpu_test::CreateANGLEGLInterface());
                 break;
 #endif // SK_ANGLE
 #if SK_COMMAND_BUFFER