GraphicsEnv: refactor to unify the debuggable logic

By default, PR_SET_DUMPABLE is 0 for zygote spawned apps, except in the
following circumstances:
1. ro.debuggable=1 (global debuggable enabled, i.e., userdebug or eng builds).
2. android:debuggable="true" in the manifest for an individual application.
3. An app which explicitly calls prctl(PR_SET_DUMPABLE, 1).
4. GraphicsEnv calls prctl(PR_SET_DUMPABLE, 1) in the presence of
   <meta-data android:name=""
   in the application manifest.

So checking both ro.debuggable=1 and PR_GET_DUMPABLE is redundant.

Bug: b/144186877, b/148566223
Test: CtsAngleIntegrationHostTestCases
Test: CtsRootlessGpuDebugHostTest
Change-Id: I934f64315b67db77ee2c2a9dff50fb23bc0a546a
Merged-In: I934f64315b67db77ee2c2a9dff50fb23bc0a546a
(cherry picked from commit 6a674c9e105bdc5d736c06a4500dcdac1c6c4006)
7 files changed