Json: Use the javascript editor for json files.

Task-number: QTCREATORBUG-4639
Change-Id: Icd0fda434d5ca66056d784dd87240db76e8a442c
Reviewed-on: http://codereview.qt-project.org/6035
Sanity-Review: Qt Sanity Bot <qt_sanity_bot@ovi.com>
Reviewed-by: Fawzi Mohamed <fawzi.mohamed@nokia.com>

src/plugins/qmljstools/qmljstoolssettings.cpp

@@ -119,6 +119,9 @@ QmlJSToolsSettings::QmlJSToolsSettings(QObject *parent)
     textEditorSettings->registerMimeTypeForLanguageId(
                 QLatin1String(Constants::JS_MIMETYPE),
                 Constants::QML_JS_SETTINGS_ID);
+    textEditorSettings->registerMimeTypeForLanguageId(
+                QLatin1String(Constants::JSON_MIMETYPE),
+                Constants::QML_JS_SETTINGS_ID);
 }
 
 QmlJSToolsSettings::~QmlJSToolsSettings()