JS: Replace hardcoded exception string with proper enum value, as declared.

Review URL: https://codereview.appspot.com/6814093

javascript/i18n/phonenumbers/phonenumberutil.js

@@ -3628,7 +3628,7 @@ i18n.phonenumbers.PhoneNumberUtil.prototype.parseHelper_ =
     throw i18n.phonenumbers.Error.NOT_A_NUMBER;
   } else if (numberToParse.length >
       i18n.phonenumbers.PhoneNumberUtil.MAX_INPUT_STRING_LENGTH_) {
-    throw 'The string supplied was too long to parse';
+    throw i18n.phonenumbers.Error.TOO_LONG;
   }
 
   /** @type {!goog.string.StringBuffer} */

javascript/i18n/phonenumbers/phonenumberutil_test.js

@@ -2210,7 +2210,7 @@ function testParseMaliciousInput() {
   } catch (e) {
     // Expected this exception.
     assertEquals('Wrong error type stored in exception.',
-                 'The string supplied was too long to parse',
+                 i18n.phonenumbers.Error.TOO_LONG,
                  e);
   }
   /** @type {!goog.string.StringBuffer} */
@@ -2226,7 +2226,7 @@ function testParseMaliciousInput() {
   } catch (e) {
     // Expected this exception.
     assertEquals('Wrong error type stored in exception.',
-                 'The string supplied was too long to parse',
+                 i18n.phonenumbers.Error.TOO_LONG,
                  e);
   }
 }