iwyu: Include callback_old.h where appropriate, final.

BUG=82098
TEST=none

Review URL: http://codereview.chromium.org/7003003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@85003 0039d316-1c4b-4281-b951-d872f2087c98
  void TestCropBack(int pos, int size) {
    CompoundBuffer cropped;
    cropped.CopyFrom(target_, 0, target_.total_bytes());
    cropped.CropBack(pos);
    EXPECT_TRUE(CompareData(cropped, data_->data(),
                            target_.total_bytes() - pos));
  }

  void TestCropBack(int pos, int size) {
    CompoundBuffer cropped;
    cropped.CopyFrom(target_, 0, target_.total_bytes());
    cropped.CropBack(pos);
    EXPECT_TRUE(CompareData(cropped, data_->data(),
                            target_.total_bytes() - pos));
  }
