Only scale fallback font if it is too big

If the drawing is rotate, then it won't be handled by the
device fallback case. So, the source glyphs can fit in
the atlas with out scaling, so don't scale. Previously,
the system would put the largest possible glyph in the
cache, and scale it down.

Change-Id: If4261854100d4736702d192e4f0847014c55f1c5
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/250796
Reviewed-by: Ben Wagner <bungeman@google.com>
Commit-Queue: Herb Derby <herb@google.com>

Author: herbderby

src/core/SkStrikeSpec.cpp

@@ -57,10 +57,12 @@ SkStrikeSpec SkStrikeSpec::MakeSourceFallback(
     SkScalar maxAtlasDimension = SkStrikeCommon::kSkSideTooBigForAtlas - 2;
 
     SkScalar runFontTextSize = font.getSize();
-
-    // Scale the text size down so the long side of all the glyphs will fit in the atlas.
-    SkScalar fallbackTextSize = SkScalarFloorToScalar(
-            (maxAtlasDimension / maxSourceGlyphDimension) * runFontTextSize);
+    SkScalar fallbackTextSize = runFontTextSize;
+    if (maxSourceGlyphDimension > maxAtlasDimension) {
+        // Scale the text size down so the long side of all the glyphs will fit in the atlas.
+        fallbackTextSize = SkScalarFloorToScalar(
+                (maxAtlasDimension / maxSourceGlyphDimension) * runFontTextSize);
+    }
 
     SkFont fallbackFont{font};
     fallbackFont.setSize(fallbackTextSize);