Remove Timer::Initialize routine

Summary:
I've run into an issue when running unit tests, where the underlying problem turned out to be
that we were creating Timer objects (through several layers of indirection) without calling
Timer::Initialize. Since Timer's thread-local storage was not properly initialized, we were
overwriting gtest's own thread-local storage, causing test failures.

Instead of requiring that every test calls Timer::Initialize(), I remove the function altogether:
The thread-local storage can be initialized on-demand, and the g_file variable initialized to
stdout and never changed, so I have simply removed it.

Reviewers: clayborg, zturner, tberghammer

Subscribers: lldb-commits

Differential Revision: http://reviews.llvm.org/D16722

llvm-svn: 259356