backout 739edf98ca0b (bug 909344) for reftest failure in layout/reftests/bugs/388367-1.html.

gfx/thebes/gfxFont.cpp

@@ -3344,14 +3344,11 @@ gfxFont::ShapeTextWithoutWordCache(gfxContext *aContext,
         }
 
         // fragment was terminated by an invalid char: skip it,
-        // unless it's a control char that we want to show as a hexbox,
         // but record where TAB or NEWLINE occur
         if (ch == '\t') {
             aTextRun->SetIsTab(aOffset + i);
         } else if (ch == '\n') {
             aTextRun->SetIsNewline(aOffset + i);
-        } else if ((ch & 0x7f) < 0x20 || ch == 0x7f) {
-            aTextRun->SetMissingGlyph(aOffset + i, ch, this);
         }
         fragStart = i + 1;
     }
@@ -3488,14 +3485,11 @@ gfxFont::SplitAndInitTextRun(gfxContext *aContext,
                      "how did we get here except via an invalid char?");
 
         // word was terminated by an invalid char: skip it,
-        // unless it's a control char that we want to show as a hexbox,
         // but record where TAB or NEWLINE occur
         if (ch == '\t') {
             aTextRun->SetIsTab(aRunStart + i);
         } else if (ch == '\n') {
             aTextRun->SetIsNewline(aRunStart + i);
-        } else if ((ch & 0x7f) < 0x20 || ch == 0x7f) {
-            aTextRun->SetMissingGlyph(aRunStart + i, ch, this);
         }
 
         hash = 0;