test_runner: Move three Mock* files into content namespace.

content/shell/renderer/test_runner/MockGrammarCheck.cpp

Index: content/shell/renderer/test_runner/MockGrammarCheck.cpp
diff --git a/content/shell/renderer/test_runner/MockGrammarCheck.cpp b/content/shell/renderer/test_runner/MockGrammarCheck.cpp
index 0744af75d31f8e78d99fec46429f197ad1ce6db7..960129a0b774730ac280abc7c364cc0aa3e72356 100644
--- a/content/shell/renderer/test_runner/MockGrammarCheck.cpp
+++ b/content/shell/renderer/test_runner/MockGrammarCheck.cpp
@@ -15,13 +15,13 @@
 using namespace blink;
 using namespace std;
 
-namespace WebTestRunner {
+namespace content {
 
 bool MockGrammarCheck::checkGrammarOfString(const WebString& text, vector<WebTextCheckingResult>* results)
 {
     DCHECK(results);
     base::string16 stringText = text;
-    if (find_if(stringText.begin(), stringText.end(), isASCIIAlpha) == stringText.end())
+    if (find_if(stringText.begin(), stringText.end(), WebTestRunner::isASCIIAlpha) == stringText.end())
         return true;
 
     // Find matching grammatical errors from known ones. This function has to
@@ -56,4 +56,4 @@ bool MockGrammarCheck::checkGrammarOfString(const WebString& text, vector<WebTex
     return false;
 }
 
-}
+}  // namespace content