Replace MockFilterCallback with MockCallback and simplify unit tests.

Replace MockFilterCallback with MockCallback and simplify unit tests.

We had a ton of unnecessarily duplicated code, most of which could be solved by introducing NewExpectedCallback().

BUG=none
TEST=media_unittests

Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=71537

[scherkus (not reviewing), 2011-01-14 02:52:26]

Cleaning up MockFilterCallback stuff.

I decided to leave in the destructor expectation (even though I'm not 100%
fan!!!) to preserve the current test expectations (they still pass!).

Instead of the bool for running the destructor callback, we end up always
running it and users can simply use a NiceMock<> if they really don't care about
it.

For CompositeFilter tests I wrote equivalent test code that uses StrictMock<>
and monitors for destruction.

[acolwell GONE FROM CHROMIUM, 2011-01-14 19:29:14]

LGTM 

I'm excited about how much code this removes. :)

http://codereview.chromium.org/6350001/diff/2001/media/base/composite_filter_...
File media/base/composite_filter_unittest.cc (right):

http://codereview.chromium.org/6350001/diff/2001/media/base/composite_filter_...
media/base/composite_filter_unittest.cc:244: EXPECT_CALL(*callback,
RunWithParams(_));
Perhaps create a ExpectRunAndDestroy() method on the mock so these 2 lines don't
have to be copied everywhere a deferred call is expected.

[scherkus (not reviewing), 2011-01-15 02:11:09]

http://codereview.chromium.org/6350001/diff/2001/media/base/composite_filter_...
File media/base/composite_filter_unittest.cc (right):

http://codereview.chromium.org/6350001/diff/2001/media/base/composite_filter_...
media/base/composite_filter_unittest.cc:244: EXPECT_CALL(*callback,
RunWithParams(_));
On 2011/01/14 19:29:14, acolwell wrote:
> Perhaps create a ExpectRunAndDestroy() method on the mock so these 2 lines
don't
> have to be copied everywhere a deferred call is expected.

I like it!  Done.