UI unit tests

[diosmosis]

We should increase our JavaScript code coverage by adding unit tests for individual UI controls. To do this, we need to:

• Allow JavaScript to be injected before taking screenshots.
• Create unit tests of all individual UI widgets (eg, site selector, datatable) that compare screenshots after triggering certain events.

[mattab]

In 5e644be: Refs #4087 #4189 We would like ui tests build to run every commit even when the Integration tests fail. This will help know exactly which commit introduced a regression.

[diosmosis]

In a68ed87: Refs #4189, use new Omni test fixture for UI tests that combines all other fixtures.

[mattab]

@capedfuzz the omni fixture broke the UI tests: https://travis-ci.org/piwik/piwik-ui-tests

[diosmosis]

In be9b410: Refs #4189, added UI unit test base class and tests for ViewDataTable. Refactored capture.js to make new type of testing possible.

[diosmosis]

In 84a22be: Refs #4189, add segment selector/editor unit tests & tweak CSS so tests look right.

[diosmosis]

In f4e39c9: Refs #4739, #4189, remove persist_fixture_data config option code, placed OmniFixture into a namespace, removed PHP screenshot testcase classes and added fixture for use w/ JavaScript screenshot tests.

[diosmosis]

In 7c7a877: Refs #4189, add Annotations.deleteAll API method, work around popover issue in phantomjs (modifying window.location.href directly erases JavaScript state for page even if the URL is the same) and tweak user creation in test fixture setup.

[diosmosis]

In 13a08d5: Refs #4189, added expected screenshot for DBStats, added actual & mock data access class to DBStats, fix bug that occurs when deleting merged assets that do not exist and fix diffviewer generation regression (expected URL was incorrect).

[diosmosis]

In 7161069: Refs #4189, add action to render site selector, add more sites for UI tests for site selector and make site selector has a margin top in UI tests.

[diosmosis]

In e1d338c: Refs #4189, add controller method to CoreHome to render period selector, add periodSelector CSS class to period selector.

[diosmosis]

In 67d34eb: Refs #4189, allow widget factory to be included in getDashboardSettingsControl() action output for tests, make sure last dashboard always overwritten by UI test start.

[diosmosis]

In 57bf5d0: Refs #4189, bug fixes for dashboard & changes to make dashboard UI tests possible. Includes:

• fix for bug where top controls not displayed correctly when dashboard is displayed in a widget iframe.
• do not display dashboard manager after dashboard action selected.
• truncate tables when running UI tests w/ --persist-fixture-data so existing database data won't be used if the fixture setup didn't complete before.
• do not create super user more than once in Fixture.
• don't include Test_Piwik_Fixture_CustomAlerts in omni fixture.
• make sure UITestFixture executes the correct code every time regardless of whether --persist-fixture-data isn't used.
• add mouseup/mousedown events to screenshot testing page rendere.
• add ability to call controller methods in screenshot tests and fix API calling mechanism.

[diosmosis]

In 8b48ff2: Refs #4189, allow screenshot tests to change viewport size.

[diosmosis]

In c8d8818: Refs #4189, allow default config file paths to be overridden for tests, rewrite proxy/index.php to use hooks for config instead of disabling dispatch.php and remove no longer used config override code.

[diosmosis]

In 8a525ad: Refs #4189, more work getting UI tests to pass and adding admin screenshots, including:

• make updatetoken.php use TestingEnvironment in testmode,
• allow persisted fixture to be dropped using new --drop command line option (for ui test runner),
• fix debugging mistake in realtime map, fix merge error in empty.twig,
• make sure Fixture prints to screen only for UI test setup, re-enable CustomAlerts fixture in OmniFixture,
• make sure forced now value for realtime map is constant,
• use *.getDatabaseConfig events to override database name in TestingEnvironment
• use TestingEnvironment in proxy/piwik.php
• add wait() method to screenshot testing framework's PageRenderer
• hide current UTC time in manage websites admin screenshot