Reland^2: Use "gfxstream" namespace

This reverts commit 222fce475152963a3171d4796e8d3491304be577.

Reland adds in aosp/2516595 which was only built on the "full"
target and removes namespace around window methods to satisfy
MacOS build.

Bug: b/271464937
Test: android build
Test: cmake build
Change-Id: I76b359cade2a5827280bccc0409333330b5f318e
4 files changed