Do not run edge extension benchmark if flag is off

Otherwise we try running the shader without compiling it first and get a
failure

Test: librenderengine_bench
Bug: 362241328
Flag: com.android.graphics.libgui.flags.edge_extension_shader
Change-Id: I9f1b4c416776cc7b4ad865d6eb64201f46a390d8
1 file changed