Fix undefined behavior in Indic dottedcircle

Chromium Issue 158998:	Conditional jump in harfbuzz-ng
http://code.google.com/p/chromium/issues/detail?id=158998

src/hb-ot-shape-complex-indic.cc

@@ -872,7 +872,7 @@ insert_dotted_circles (const hb_ot_shape_plan_t *plan,
   if (!font->get_glyph (0x25CC, 0, &dottedcircle_glyph))
     return;
 
-  hb_glyph_info_t dottedcircle;
+  hb_glyph_info_t dottedcircle = {0};
   dottedcircle.codepoint = 0x25CC;
   set_indic_properties (dottedcircle);
   dottedcircle.codepoint = dottedcircle_glyph;