bug 590114 - treat unresolved common script runs as Latin. r=jdaggett approval2.0=joe

gfx/thebes/gfxFont.cpp

@@ -2209,6 +2209,13 @@ gfxFontGroup::InitTextRun(gfxContext *aContext,
     PRUint32 runStart = 0, runLimit = aLength;
     PRInt32 runScript = HB_SCRIPT_LATIN;
     while (scriptRuns.Next(runStart, runLimit, runScript)) {
+        if (runScript <= HB_SCRIPT_INHERITED) {
+            // For unresolved "common" or "inherited" runs, default to Latin
+            // for now.
+            // (Should we somehow use the language or locale to try and infer
+            // a better default?)
+            runScript = HB_SCRIPT_LATIN;
+        }
         InitTextRun(aContext, aTextRun, aString, aLength,
                     runStart, runLimit, runScript);
     }