Removes JS_STR_CHARS as a contentkind in soy.

Removes several tests which were testing this contentkind.
-------------
Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=73417913

closure/goog/soy/data.js

@@ -21,7 +21,6 @@
  * @author gboyer@google.com (Garrett Boyer)
  */
 
-goog.provide('goog.soy.data');
 goog.provide('goog.soy.data.SanitizedContent');
 goog.provide('goog.soy.data.SanitizedContentKind');
 
@@ -55,20 +54,6 @@ goog.soy.data.SanitizedContentKind = {
    */
   JS: goog.DEBUG ? {sanitizedContentJsChars: true} : {},
 
-  /**
-   * A sequence of code units that can appear between quotes (either kind) in a
-   * JS program without causing a parse error, and without causing any side
-   * effects.
-   * <p>
-   * The content should not contain unescaped quotes, newlines, or anything else
-   * that would cause parsing to fail or to cause a JS parser to finish the
-   * string its parsing inside the content.
-   * <p>
-   * The content must also not end inside an escape sequence ; no partial octal
-   * escape sequences or odd number of '{@code \}'s at the end.
-   */
-  JS_STR_CHARS: goog.DEBUG ? {sanitizedContentJsStrChars: true} : {},
-
   /** A properly encoded portion of a URI. */
   URI: goog.DEBUG ? {sanitizedContentUri: true} : {},