wm tracing: decouple perfetto WM tracing and dump flags

Use dedicated flag to enable/disable perfetto WM dump,
thus decoupling the deployment of perfetto WM tracing and
perfetto WM dump. Needed till the jank regression (b/362327824)
(triggered by perfetto WM dump) is fully understood and the
jank test suite is fixed accordingly.

Bug: 323165543
Flag: android.tracing.perfetto_wm_tracing
Test: presubmit

Change-Id: I8d41b41c3c682e14b1b0c8781a3cddbd2d82e4d0
4 files changed