SimpleFontData::fillGlyphPage should not set zero for missing glyphs

Source/platform/fonts/mac/SimpleFontDataCoreText.cpp

Index: Source/platform/fonts/mac/SimpleFontDataCoreText.cpp
diff --git a/Source/platform/fonts/mac/SimpleFontDataCoreText.cpp b/Source/platform/fonts/mac/SimpleFontDataCoreText.cpp
index b1940d0effecfa753f4b8322551cc131a3145a70..e3b0b86a380881df4fb2f31582a8699eda766ca4 100644
--- a/Source/platform/fonts/mac/SimpleFontDataCoreText.cpp
+++ b/Source/platform/fonts/mac/SimpleFontDataCoreText.cpp
@@ -105,9 +105,7 @@ bool SimpleFontData::fillGlyphPage(GlyphPage* pageToFill, unsigned offset, unsig
     if (!shouldUseCoreText(buffer, bufferLength, this)) {
         CGFontGetGlyphsForUnichars(platformData().cgFont(), buffer, glyphs.data(), bufferLength);
         for (unsigned i = 0; i < length; ++i) {
-            if (!glyphs[i]) {
-                pageToFill->setGlyphDataForIndex(offset + i, 0, 0);
-            } else {
+            if (glyphs[i]) {
                 pageToFill->setGlyphDataForIndex(offset + i, glyphs[i], this);
                 haveGlyphs = true;
             }
@@ -118,9 +116,7 @@ bool SimpleFontData::fillGlyphPage(GlyphPage* pageToFill, unsigned offset, unsig
         // places the glyphs at indices corresponding to the first character of each pair.
         unsigned glyphStep = bufferLength / length;
         for (unsigned i = 0; i < length; ++i) {
-            if (!glyphs[i * glyphStep]) {
-                pageToFill->setGlyphDataForIndex(offset + i, 0, 0);
-            } else {
+            if (glyphs[i * glyphStep]) {
                 pageToFill->setGlyphDataForIndex(offset + i, glyphs[i * glyphStep], this);
                 haveGlyphs = true;
             }
@@ -134,10 +130,6 @@ bool SimpleFontData::fillGlyphPage(GlyphPage* pageToFill, unsigned offset, unsig
         CFArrayRef runArray = CTLineGetGlyphRuns(line.get());
         CFIndex runCount = CFArrayGetCount(runArray);
 
-        // Initialize glyph entries
-        for (unsigned index = 0; index < length; ++index)
-            pageToFill->setGlyphDataForIndex(offset + index, 0, 0);
-
         Vector<CGGlyph, 512> glyphVector;
         Vector<CFIndex, 512> indexVector;
         bool done = false;