Define DISALLOW_COPY_AND_ASSIGN only if is undefined.

Other libraries define this macro already (libnativehelper for example).
We already have a guard there to ensure we don't define the macros
twice. We should have one in libchrome too.

Bug: 25862968

Change-Id: I2e238eb06d58c3877745841ec1f7da79bf58a34e
1 file changed