Make existing unit tests only run on GL contexts

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1869503002

Review URL: https://codereview.chromium.org/1869503002
diff --git a/tests/TextBlobCacheTest.cpp b/tests/TextBlobCacheTest.cpp
index d13d251..8f95cf0 100644
--- a/tests/TextBlobCacheTest.cpp
+++ b/tests/TextBlobCacheTest.cpp
@@ -156,19 +156,19 @@
     draw(canvas, 1, blobs);
 }
 
-DEF_GPUTEST_FOR_NULL_CONTEXT(TextBlobCache, reporter, ctxInfo) {
+DEF_GPUTEST_FOR_NULLGL_CONTEXT(TextBlobCache, reporter, ctxInfo) {
     text_blob_cache_inner(reporter, ctxInfo.fGrContext, 1024, 256, 30, true, false);
 }
 
-DEF_GPUTEST_FOR_NULL_CONTEXT(TextBlobStressCache, reporter, ctxInfo) {
+DEF_GPUTEST_FOR_NULLGL_CONTEXT(TextBlobStressCache, reporter, ctxInfo) {
     text_blob_cache_inner(reporter, ctxInfo.fGrContext, 256, 256, 10, true, true);
 }
 
-DEF_GPUTEST_FOR_NULL_CONTEXT(TextBlobAbnormal, reporter, ctxInfo) {
+DEF_GPUTEST_FOR_NULLGL_CONTEXT(TextBlobAbnormal, reporter, ctxInfo) {
     text_blob_cache_inner(reporter, ctxInfo.fGrContext, 256, 256, 10, false, false);
 }
 
-DEF_GPUTEST_FOR_NULL_CONTEXT(TextBlobStressAbnormal, reporter, ctxInfo) {
+DEF_GPUTEST_FOR_NULLGL_CONTEXT(TextBlobStressAbnormal, reporter, ctxInfo) {
     text_blob_cache_inner(reporter, ctxInfo.fGrContext, 256, 256, 10, false, true);
 }
 #endif