gl/test: Move some initialization code used in tests to a separate component.

Moving test-code to a separete component, so that adding more test-only
dependencies does not affect non-test code.

BUG=none
CQ_INCLUDE_TRYBOTS=tryserver.blink:linux_blink_rel
TBR=jam@ for non-ui/gl/ changes, since trivial #include/gyp-gn updates

Review URL: https://codereview.chromium.org/1238443004

Cr-Commit-Position: refs/heads/master@{#339539}

• android_webview/android_webview_tests.gypi[diff]
• android_webview/lib/main/webview_tests.cc[diff]
• ash/accelerators/accelerator_interactive_uitest_chromeos.cc[diff]
• ash/drag_drop/drag_drop_interactive_uitest.cc[diff]
• ash/test/test_suite.cc[diff]
• ash/wm/ash_native_cursor_manager_interactive_uitest.cc[diff]
• cc/BUILD.gn[diff]
• cc/cc_tests.gyp[diff]
• cc/test/cc_test_suite.cc[diff]
• chrome/chrome_tests_unit.gypi[diff]
• chrome/test/base/chrome_unit_test_suite.cc[diff]
• components/test/DEPS[diff]
• components/test/run_all_unittests.cc[diff]
• components/view_manager/BUILD.gn[diff]
• components/view_manager/view_manager_app.cc[diff]
• content/content_tests.gypi[diff]
• content/test/BUILD.gn[diff]
• content/test/content_test_suite.cc[diff]
• extensions/test/extensions_unittests_main.cc[diff]
• gpu/BUILD.gn[diff]
• gpu/command_buffer/service/gles2_cmd_decoder_unittest_base.cc[diff]
• gpu/command_buffer/service/gpu_service_test.cc[diff]
• gpu/config/gpu_info_collector_unittest.cc[diff]
• gpu/gpu.gyp[diff]
• ui/app_list/test/DEPS[diff]
• ui/app_list/test/run_all_unittests.cc[diff]
• ui/aura/test/run_all_unittests.cc[diff]
• ui/chromeos/run_all_unittests.cc[diff]
• ui/chromeos/touch_exploration_controller_unittest.cc[diff]
• ui/compositor/test/in_process_context_factory.cc[diff]
• ui/compositor/test/test_suite.cc[diff]
• ui/gl/BUILD.gn[diff]
• ui/gl/gl.gyp[diff]
• ui/gl/gl_implementation.h[diff]
• ui/gl/gl_surface.cc[diff]
• ui/gl/gl_surface.h[diff]
• ui/gl/gl_tests.gyp[diff]
• ui/gl/gpu_timing_unittest.cc[diff]
• ui/gl/test/gl_surface_test_support.cc[Added - diff]
• ui/gl/test/gl_surface_test_support.h[Added - diff]
• ui/keyboard/DEPS[diff]
• ui/keyboard/test/run_all_unittests.cc[diff]
• ui/message_center/test/DEPS[diff]
• ui/message_center/test/run_all_unittests.cc[diff]
• ui/views/DEPS[diff]
• ui/views/corewm/desktop_capture_controller_unittest.cc[diff]
• ui/views/run_all_unittests.cc[diff]
• ui/views/widget/desktop_aura/desktop_window_tree_host_x11_interactive_uitest.cc[diff]
• ui/views/widget/desktop_aura/x11_topmost_window_finder_interactive_uitest.cc[diff]
• ui/views/widget/widget_interactive_uitest.cc[diff]
• ui/wm/test/run_all_unittests.cc[diff]