Add missing delayTestFinish() to GwtServletBaseTest.

Change-Id: I9e47d29e9ea6903f45fc8e786f143c09b0a1e683
Review-Link: https://gwt-review.googlesource.com/#/c/2180/

Review by: skybrian@google.com
Adds stack traces to printStackTrace in java/lang/Throwable emulation.

Fixes issue 2469

Change-Id: I2a5a05d8574c1e6d86b004de4ab7d90ad96d587a
Review-Link: https://gwt-review.googlesource.com/#/c/2130/

Review by: skybrian@google.com
Make ConsoleLogHandler use console.error/warn/info.

Deprecate FirebugLogHandler, but keep it there for backwards compatibility.

Fixes issue 6916 and issue 8040

Change-Id: I65c26c010d2e5e2fa96a4fbbffd1229c7a09f5fe
Review-Link: https://gwt-review.googlesource.com/#/c/2060/

Review by: skybrian@google.com