Allow small-caps synthesis for @font-face with multiple sources including SVG format

LayoutTests/fast/css/font-face-small-caps-with-svg-source-expected.html

 <style>
     @font-face {
         font-family: family1;
-        src: local(Ahem), url(../../resources/Ahem.ttf);
-        font-variant: small-caps;
+        src: local(Ahem),
+             url(../../resources/Ahem.ttf) format(truetype);
     }
     p.test {
         font-family: family1;
         font-variant: small-caps;
     }
 </style>
 <p>
-Tests that if @font-face does not provide an explicit font-variant, normal is used.
+Test for <a href="http://crbug.com/298970">bug 298970</a>. Verifies that small-caps synthesis works when @font-face has a svg source.
 </p>
 <p>
 The text below should be a series of black boxes.
 </p>
 <p class="test">failure</p>