style(): improve comments and variable names

Fix bad variable names.

 References angular#9869

src/core/services/theming/theming.js

@@ -1011,15 +1011,15 @@ function generateAllThemes($injector, $mdTheming) {
     for (var i = 0; i < themeCss.length; i++) {
       var character = themeCss.charAt(i);
 
-      // Check for quoted content
+      // Check for content in quotes
       if (character === '\'' || character === '\"') {
         var pattern = '\\' + character + '.*' + '\\' + character;
         var regex = new RegExp(pattern);
-        // Get quoted content
-        var quotedText = regex.exec(themeCss.slice(i)).toString();
-        currentRule += quotedText;
+        // Get content in quotes
+        var textInQuotes = regex.exec(themeCss.slice(i)).toString();
+        currentRule += textInQuotes;
         // Jump to the closing quote char
-        i += quotedText.length;
+        i += textInQuotes.length;
       } else {
         currentRule += character;