Migrate legacy perf dashboard tests to mocha.js based tests

Migrate legacy perf dashboard tests to mocha.js based tests
https://bugs.webkit.org/show_bug.cgi?id=156335

Reviewed by Chris Dumez.

Migrated all legacy run-tests.js tests to mocha.js based tests. Since the new harness uses Promise
for most of asynchronous operations, refactored the tests to use Promises as well, and added more
assertions where appropriate.

Also consolidated common helper functions into server-tests/resources/common-operations.js.
Unfortunately there were multiple inconsistent implementations of addBuilder/addSlave. Some were
taking an array of reports while others were taking a single report. New shared implementation in
common-operations.js now takes a single report.

Also decreased the timeout in most tests from 10s to 1s so that tests fail early when they timeout.
Most of tests are passing under 100ms on my computer so 1s should be plenty still.

* run-tests.js: Removed.
* server-tests/admin-platforms-tests.js: Moved from tests/admin-platforms.js.
(reportsForDifferentPlatforms):
* server-tests/admin-reprocess-report-tests.js: Moved from tests/admin-reprocess-report.js.
(.addBuilder): Moved to common-operations.js.
* server-tests/api-build-requests-tests.js:
* server-tests/api-manifest.js: Use MockData.resetV3Models() instead of manually clearing maps.
* server-tests/api-measurement-set-tests.js: Moved from tests/api-measurement-set.js.
(.queryPlatformAndMetric):
(.format):
* server-tests/api-report-commits-tests.js: Moved from tests/api-report-commits.js.
* server-tests/api-report-tests.js: Moved from tests/api-report.js.
(.emptyReport):
(.emptySlaveReport):
(.reportWithSameSubtestName):
* server-tests/resources/common-operations.js: Added.
(addBuilderForReport): Extracted from tests.
(addSlaveForReport): Ditto.
(connectToDatabaseInEveryTest): Added.
(submitReport): Extracted from admin-platforms-tests.js.
* server-tests/resources/test-server.js:
(TestServer): Make TestServer a singleton since it doesn't make any sense for each module to start
its own Apache instance (that would certainly will fail).
* server-tests/tools-buildbot-triggerable-tests.js:
* tests: Removed.
* tools/js/database.js:
(Database.prototype.selectAll): Added.
(Database.prototype.selectFirstRow): Added.
(Database.prototype.selectRows): Added. Dynamically construct a query string based on arguments.

git-svn-id: https://svn.webkit.org/repository/webkit/trunk@199191 268f45cc-cd09-0410-ab3c-d52691b4dbfc