tcmalloc: remove support for runtime selection of stack unwinding method

The new tcmalloc added support for selecting the stack unwinding method at
runtime. This support adds 20 static initializers to the chrome binary and
is unnecessary for Chromium use cases.
This patch puts the runtime selection support behind ifdefs. By default,
the stack unwind method is statically selected at compile time.

BUG=b:119055819
TEST=Unit tests pass

Change-Id: I5b42248a38f1765d8bcb50b34448b3e0c434d953
Reviewed-on: https://chromium-review.googlesource.com/c/1453096
Commit-Queue: Gabriel Marin <gmx@chromium.org>
Reviewed-by: Will Harris <wfh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#631422}
1 file changed