Fix incorrect return value on missing glyph

The GetGlyph function returns a boolean indicating whether the glyph
exists in the font. However, we were testing the pointer, so the test
would always succeed even if the glyph was missing. This interfered with
fallback algorithms for rendering compatibility characters.

Bug: 15816880
Bug: 16856221
Change-Id: I95cd45bb8f5e8ddf74cf23e6e624fbf30172e00a
diff --git a/core/jni/android/graphics/MinikinSkia.cpp b/core/jni/android/graphics/MinikinSkia.cpp
index ae29014..4649b07 100644
--- a/core/jni/android/graphics/MinikinSkia.cpp
+++ b/core/jni/android/graphics/MinikinSkia.cpp
@@ -39,7 +39,7 @@
     uint16_t glyph16;
     paint.textToGlyphs(&codepoint, sizeof(codepoint), &glyph16);
     *glyph  = glyph16;
-    return !!glyph;
+    return !!glyph16;
 }
 
 static void MinikinFontSkia_SetSkiaPaint(const MinikinFont* font, SkPaint* skPaint, const MinikinPaint& paint) {