Revert "Revert "Redefine the meaning of sample counts in GPU backend.""

Fixes gpu config default samples to be 1 and updates config parsing test accordingly.

This reverts commit c1ce2f7966babaae0deb150f93f1227ee5af9285.

Bug: skia:
Change-Id: I456973b1f52ced85a2011ea10fc49449bfc5846f
Reviewed-on: https://skia-review.googlesource.com/102147
Reviewed-by: Brian Salomon <bsalomon@google.com>
Commit-Queue: Brian Salomon <bsalomon@google.com>
diff --git a/tools/fiddle/fiddle_main.cpp b/tools/fiddle/fiddle_main.cpp
index 4ba84f3..684bc2a 100644
--- a/tools/fiddle/fiddle_main.cpp
+++ b/tools/fiddle/fiddle_main.cpp
@@ -133,7 +133,7 @@
     backingDesc.fHeight = bm.height();
     // This config must match the SkColorType used in draw.cpp in the SkImage and Surface factories
     backingDesc.fConfig = kRGBA_8888_GrPixelConfig;
-    backingDesc.fSampleCnt = 0;
+    backingDesc.fSampleCnt = 1;
 
     if (!bm.empty()) {
         SkPixmap originalPixmap;