Initialize bounds even if the text length is zero.

src/core/SkPaint.cpp

Index: src/core/SkPaint.cpp
diff --git a/src/core/SkPaint.cpp b/src/core/SkPaint.cpp
index 9510e75c75a88ad425bb8cbdd4aa017d2edb1f61..07d1c33bd47b747f3711be4fe75a988b0f98a08b 100644
--- a/src/core/SkPaint.cpp
+++ b/src/core/SkPaint.cpp
@@ -1071,6 +1071,9 @@ SkScalar SkPaint::measureText(const void* textData, size_t length,
                 bounds->fBottom = SkScalarMul(bounds->fBottom, scale);
             }
         }
+    } else if (bounds) {
+        // ensure that even if we don't measure_text we still update the bounds
+        bounds->setEmpty();
     }
     return width;
 }