Fix tests requiring package.json at the root of the project

As projectChangesService now checks the package.json at the root of the project, several tests are failing as they are mocking the project creation and there's no package.json at the specified place.
Fix this by creating the package.json in the tests.

Author: rosen-vladimirov

test/platform-service.ts

@@ -49,6 +49,9 @@ function createTestInjector() {
 	testInjector.register("nodeModulesBuilder", {
 		prepareNodeModules: () => {
 			return Promise.resolve();
+		},
+		prepareJSNodeModules: () => {
+			return Promise.resolve();
 		}
 	});
 	testInjector.register("pluginsService", {
@@ -382,6 +385,12 @@ describe('Platform Service Tests', () => {
 
 			let appDestFolderPath = path.join(tempFolder, "appDest");
 			let appResourcesFolderPath = path.join(appDestFolderPath, "App_Resources");
+			fs.writeJson(path.join(tempFolder, "package.json"), {
+				name: "testname",
+				nativescript: {
+					id: "org.nativescript.testname"
+				}
+			});
 
 			return { tempFolder, appFolderPath, app1FolderPath, appDestFolderPath, appResourcesFolderPath };
 		}

test/project-changes-service.ts

@@ -32,6 +32,13 @@ class ProjectChangesServiceTest extends BaseServiceTest {
 		this.injector.register("devicePlatformsConstants", {});
 		this.injector.register("projectChangesService", ProjectChangesService);
 
+		const fs = this.injector.resolve<IFileSystem>("fs");
+		fs.writeJson(path.join(this.projectDir, Constants.PACKAGE_JSON_FILE_NAME), {
+			nativescript: {
+				id: "org.nativescript.test"
+			}
+		});
+
 	}
 
 	get projectChangesService(): IProjectChangesService {