chore: remove support for ubuntu platform (#111)

diff --git a/spec/ConfigChanges/ConfigFile.spec.js b/spec/ConfigChanges/ConfigFile.spec.js
index a28c427..00d38c3 100644
--- a/spec/ConfigChanges/ConfigFile.spec.js
+++ b/spec/ConfigChanges/ConfigFile.spec.js
@@ -78,11 +78,6 @@
     });
 
     it('resolveConfigFilePath should return file path', function () {
-        var configPath = path.join('project_dir', 'config.xml');
-        expect(configFile.resolveConfigFilePath('project_dir', 'ubuntu', 'config.xml')).toBe(configPath);
-    });
-
-    it('resolveConfigFilePath should return file path', function () {
         var file = path.join('res', 'xml');
         var configPath = path.join('project_dir', 'app', 'src', 'main', file, 'xml');
         expect(configFile.resolveConfigFilePath('project_dir', 'android', file)).toBe(configPath);
diff --git a/src/ConfigChanges/ConfigFile.js b/src/ConfigChanges/ConfigFile.js
index 626e410..83a0295 100644
--- a/src/ConfigChanges/ConfigFile.js
+++ b/src/ConfigChanges/ConfigFile.js
@@ -211,9 +211,7 @@
     // be resolved to the real location of the file.
     // TODO: Move this out of cordova-common into platforms
     if (file === 'config.xml') {
-        if (platform === 'ubuntu') {
-            filepath = path.join(project_dir, 'config.xml');
-        } else if (platform === 'ios' || platform === 'osx') {
+        if (platform === 'ios' || platform === 'osx') {
             filepath = path.join(
                 project_dir,
                 module.exports.getIOSProjectname(project_dir),