Choose a less evil scale factor texel_subset_nearest_upscale decal tests

The existing scale factor put the decal edge exactly on a pixel center
causing some jaggies as different row columns has slightly different
interpolated values and fell on different sides of the decal edge,

Change-Id: I396395f68366e3cfc3b0c0ce11466c43dd4e60ea
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/268306
Reviewed-by: Brian Salomon <bsalomon@google.com>
Commit-Queue: Brian Salomon <bsalomon@google.com>
diff --git a/gm/texelsubset.cpp b/gm/texelsubset.cpp
index febf3d0..215c5a7 100644
--- a/gm/texelsubset.cpp
+++ b/gm/texelsubset.cpp
@@ -104,7 +104,7 @@
         SkTArray<SkMatrix> textureMatrices;
 
         SkRect a = SkRect::Make(texelSubset);
-        SkRect b = fUpscale ? a.makeInset (.30f * a.width(), .30f * a.height())
+        SkRect b = fUpscale ? a.makeInset (.31f * a.width(), .31f * a.height())
                             : a.makeOutset(.25f * a.width(), .25f * a.height());
         textureMatrices.push_back().setRectToRect(a, b, SkMatrix::kFill_ScaleToFit);