Fix: doRunAdvance returns wrong value when offset == count.

Bug: 27869952
Change-Id: I56278676da4c354ced4244e4b073bb0d82edf93b
diff --git a/core/jni/android/graphics/Paint.cpp b/core/jni/android/graphics/Paint.cpp
index d00e94c..f00f0bf 100644
--- a/core/jni/android/graphics/Paint.cpp
+++ b/core/jni/android/graphics/Paint.cpp
@@ -823,7 +823,7 @@
     static jfloat doRunAdvance(const Paint* paint, TypefaceImpl* typeface, const jchar buf[],
             jint start, jint count, jint bufSize, jboolean isRtl, jint offset) {
         int bidiFlags = isRtl ? kBidi_Force_RTL : kBidi_Force_LTR;
-        if (offset == count) {
+        if (offset == start + count) {
             return MinikinUtils::measureText(paint, bidiFlags, typeface, buf, start, count,
                     bufSize, nullptr);
         }