Use SkTileMode instead of nested enum

Add guard to transition clients

Change-Id: Ia7a3e8f95722f91e84af262168dadf89a78707da
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/205720
Reviewed-by: Mike Reed <reed@google.com>
Commit-Queue: Mike Reed <reed@google.com>
Auto-Submit: Mike Reed <reed@google.com>
diff --git a/docs/examples/Src_Over.cpp b/docs/examples/Src_Over.cpp
index 1381150..e0c9fb3 100644
--- a/docs/examples/Src_Over.cpp
+++ b/docs/examples/Src_Over.cpp
@@ -8,13 +8,13 @@
     SkPoint horz[] = { { 0, 0 }, { 256, 0 } };
     SkPaint paint;
     paint.setShader(SkGradientShader::MakeLinear(horz, colors, nullptr, SK_ARRAY_COUNT(colors),
-            SkShader::kClamp_TileMode));
+            SkTileMode::kClamp));
     canvas->drawPaint(paint);
     paint.setBlendMode(SkBlendMode::kDstIn);
     SkColor alphas[] = { SK_ColorBLACK, SK_ColorTRANSPARENT };
     SkPoint vert[] = { { 0, 0 }, { 0, 256 } };
     paint.setShader(SkGradientShader::MakeLinear(vert, alphas, nullptr, SK_ARRAY_COUNT(alphas),
-            SkShader::kClamp_TileMode));
+            SkTileMode::kClamp));
     canvas->drawPaint(paint);
     canvas->clipRect( { 30, 30, 226, 226 } );
     canvas->drawColor(SkColorSetA(SK_ColorGREEN, 128), SkBlendMode::kSrcOver);