Rename enums in GrContextFactory to remove "GL"

Also, remove kNative as a separate context type and instead make it an alias for kGL or kGLES based on OS.

GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1845923004

Committed: https://skia.googlesource.com/skia/+/2d9c6f81353597aebf5934547e5cba7a872196fb

Review URL: https://codereview.chromium.org/1845923004
diff --git a/dm/DMSrcSink.cpp b/dm/DMSrcSink.cpp
index 5f8727f..0862967 100644
--- a/dm/DMSrcSink.cpp
+++ b/dm/DMSrcSink.cpp
@@ -941,8 +941,8 @@
 
 DEFINE_bool(gpuStats, false, "Append GPU stats to the log for each GPU task?");
 
-GPUSink::GPUSink(GrContextFactory::GLContextType ct,
-                 GrContextFactory::GLContextOptions options,
+GPUSink::GPUSink(GrContextFactory::ContextType ct,
+                 GrContextFactory::ContextOptions options,
                  int samples,
                  bool diText,
                  SkColorType colorType,