Fix bug #5901103 all_source_project_146981_Android - Android ICS LQA Regression:FA, AR, HE and TH - Font Corruption

- use the first char of the "run" instead of the "string" for the BaseGlyphCount

Change-Id: I647528ec912bb69655cf301bbc73b66dc1a6fc82

Author: Fabrice Di Meglio

core/jni/android/graphics/TextLayoutCache.cpp

@@ -811,7 +811,7 @@ size_t TextLayoutEngine::shapeFontRun(SkPaint* paint, bool isRTL) {
     case HB_Script_Hebrew:
     case HB_Script_Bengali:
     case HB_Script_Thai:{
-        const uint16_t* text16 = (const uint16_t*)mShaperItem.string;
+        const uint16_t* text16 = (const uint16_t*)(mShaperItem.string + mShaperItem.item.pos);
         SkUnichar firstUnichar = SkUTF16_NextUnichar(&text16);
         baseGlyphCount = paint->getBaseGlyphCount(firstUnichar);
         break;