Bug 4573. Was not dealing with the case where only a scalable font was

available (no bitmap fonts). Fixed.

gfx/src/gtk/nsFontMetricsGTK.cpp

@@ -1310,12 +1310,16 @@ void
 PickASizeAndLoad(nsFontSearch* aSearch, nsFontStretch* aStretch,
   nsFontCharSet* aCharSet)
 {
-  nsFontGTK* s;
-  nsFontGTK* begin = aStretch->mSizes;
-  nsFontGTK* end = &aStretch->mSizes[aStretch->mSizesCount];
+  nsFontGTK* s = nsnull;
+  nsFontGTK* begin;
+  nsFontGTK* end;
   nsFontMetricsGTK* m = aSearch->mMetrics;
   int desiredSize = m->mPixelSize;
+  int scalable = 0;
 
+  if (aStretch->mSizes) {
+    begin = aStretch->mSizes;
+    end = &aStretch->mSizes[aStretch->mSizesCount];
     for (s = begin; s < end; s++) {
       if (s->mSize >= desiredSize) {
         break;
@@ -1380,6 +1384,15 @@ PickASizeAndLoad(nsFontSearch* aSearch, nsFontStretch* aStretch,
     if (aStretch->mScalable) {
       double ratio = (s->mActualSize / ((double) desiredSize));
       if ((ratio > 1.2) || (ratio < 0.8)) {
+        scalable = 1;
+      }
+    }
+  }
+  else {
+    scalable = 1;
+  }
+
+  if (scalable) {
     begin = aStretch->mScaledFonts;
     end = &aStretch->mScaledFonts[aStretch->mScaledFontsCount];
     for (s = begin; s < end; s++) {
@@ -1418,7 +1431,6 @@ PickASizeAndLoad(nsFontSearch* aSearch, nsFontStretch* aStretch,
       }
     }
   }
-  }
 
   if (m->mLoadedFontsCount == m->mLoadedFontsAlloc) {
     int newSize;