Revert "Use the optimize_for_size property instead of "-Os" cflag"

This reverts commit 464305040a0ff5539a8ba958d18e08554bba0b46.

This change exposed a mis-compile in clang-r547379. The crash is not
observed with -Os. Reverting as a temporary mitigation.

Bug: 396682028
Change-Id: If0bff97ab1f0f86f5e53c32181cd546498ed13c5
1 file changed