add a standalone angle gclient config

To be used in https://chromium-review.googlesource.com/c/chromium/tools/build/+/984433

Bug: 820421
Change-Id: I76d32ed9f7b5caa256bfa85220ac0c256bbc1a48
Reviewed-on: https://chromium-review.googlesource.com/984692
Reviewed-by: Robbie Iannucci <iannucci@chromium.org>
Commit-Queue: Nico Weber <thakis@chromium.org>
Commit-Queue: Robbie Iannucci <iannucci@chromium.org>

recipes/README.recipes.md

@@ -740,7 +740,7 @@ like checkout or compile), and some of these tests have failed.
 
 [DEPS](/recipes/recipe_modules/gclient/examples/full.py#5): [gclient](#recipe_modules-gclient), [recipe\_engine/context][recipe_engine/recipe_modules/context], [recipe\_engine/path][recipe_engine/recipe_modules/path], [recipe\_engine/properties][recipe_engine/recipe_modules/properties], [recipe\_engine/step][recipe_engine/recipe_modules/step]
 
-— **def [RunSteps](/recipes/recipe_modules/gclient/examples/full.py#45)(api):**
+— **def [RunSteps](/recipes/recipe_modules/gclient/examples/full.py#46)(api):**
 ### *recipes* / [gclient:tests/patch\_project](/recipes/recipe_modules/gclient/tests/patch_project.py)
 
 [DEPS](/recipes/recipe_modules/gclient/tests/patch_project.py#9): [gclient](#recipe_modules-gclient), [recipe\_engine/properties][recipe_engine/recipe_modules/properties]

recipes/recipe_modules/gclient/config.py

@@ -383,3 +383,9 @@ def gerrit_test_cq_normal(c):
   soln = c.solutions.add()
   soln.name = 'gerrit-test-cq-normal'
   soln.url = 'https://chromium.googlesource.com/playground/gerrit-cq/normal.git'
+
+@config_ctx()
+def angle(c):
+  soln = c.solutions.add()
+  soln.name = 'angle'
+  soln.url = 'https://chromium.googlesource.com/angle/angle.git'

recipes/recipe_modules/gclient/examples/full.py

@@ -13,6 +13,7 @@ DEPS = [
 
 TEST_CONFIGS = [
   'android',
+  'angle',
   'boringssl',
   'build_internal',
   'build_internal_scripts_slave',