Remove testRunner.injectStyleSheet usage from layout tests.

LayoutTests/css3/device-adapt/viewport-initial-width-zero.html

Index: LayoutTests/css3/device-adapt/viewport-initial-width-zero.html
diff --git a/LayoutTests/css3/device-adapt/viewport-initial-width-zero.html b/LayoutTests/css3/device-adapt/viewport-initial-width-zero.html
index 63c32c417655280d4a5e026b3072858d873c1c2c..8fa624cf1196660c19cf357f673848b1a977a414 100644
--- a/LayoutTests/css3/device-adapt/viewport-initial-width-zero.html
+++ b/LayoutTests/css3/device-adapt/viewport-initial-width-zero.html
@@ -10,9 +10,6 @@
         }
     </style>
     <script type="text/javascript">
-        if (window.testRunner)

[dcheng, 2015/04/02 04:41:18]

The injected style sheet didn't look particularly relevant to the test, so I
just removed it. In fact, this block seemed to be pointless for most of these
tests, so I'm not really sure why it was in a lot of these tests.

-            testRunner.injectStyleSheet("@viewport { width: extend-to-zoom 980px; min-zoom: 0.25; max-zoom: 5; height: auto; zoom: auto; user-zoom: zoom; orientation: auto }", true);
-
         function test() {
             if (window.testRunner) {
                 testRunner.dumpAsText();