Reland "Remove ANGLE recipe config."

This is a reland of b8686d2622
Must land after https://crrev.com/c/2831999

Original change's description:
> Remove ANGLE recipe config.
>
> This config is now located in the ANGLE recipe_module.
>
> Bug: angleproject:5114
> Change-Id: I2c4cc51dafeb94378056c135538d0d13bac9c8cb
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/2826242
> Auto-Submit: Jamie Madill <jmadill@chromium.org>
> Commit-Queue: Andrii Shyshkalov <tandrii@google.com>
> Reviewed-by: Andrii Shyshkalov <tandrii@google.com>

Bug: angleproject:5114
Change-Id: I858d50f49466707eae7194fd82713de7b0b2e6d6
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/2835386
Reviewed-by: Dirk Pranke <dpranke@google.com>
Commit-Queue: Jamie Madill <jmadill@chromium.org>

recipes/README.recipes.md

@@ -1008,7 +1008,7 @@ Raises:
 
 [DEPS](/recipes/recipe_modules/gclient/examples/full.py#5): [gclient](#recipe_modules-gclient), [recipe\_engine/buildbucket][recipe_engine/recipe_modules/buildbucket], [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#54)(api):**
+— **def [RunSteps](/recipes/recipe_modules/gclient/examples/full.py#53)(api):**
 ### *recipes* / [gclient:tests/diff\_deps](/recipes/recipe_modules/gclient/tests/diff_deps.py)
 
 [DEPS](/recipes/recipe_modules/gclient/tests/diff_deps.py#7): [gclient](#recipe_modules-gclient), [recipe\_engine/assertions][recipe_engine/recipe_modules/assertions], [recipe\_engine/buildbucket][recipe_engine/recipe_modules/buildbucket], [recipe\_engine/path][recipe_engine/recipe_modules/path], [recipe\_engine/platform][recipe_engine/recipe_modules/platform], [recipe\_engine/properties][recipe_engine/recipe_modules/properties], [recipe\_engine/raw\_io][recipe_engine/recipe_modules/raw_io]

recipes/recipe_modules/gclient/config.py

@@ -405,19 +405,6 @@ def gerrit_test_cq_normal(c):
   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'
-  # Standalone developer angle builds want the angle checkout in the same
-  # directory the .gclient file is in.  Bots want it in a directory called
-  # 'angle'.  To make both cases work, the angle DEPS file pulls deps and runs
-  # hooks relative to the variable "root" which is set to . by default and
-  # then to 'angle' in the recipes here:
-  soln.custom_vars = {'angle_root': 'angle'}
-  c.got_revision_mapping['angle'] = 'got_revision'
-
 @config_ctx()
 def dawn(c):
   soln = c.solutions.add()

recipes/recipe_modules/gclient/examples/full.py

@@ -14,7 +14,6 @@ DEPS = [
 
 TEST_CONFIGS = [
   'android',
-  'angle',
   'boringssl',
   'build_internal',
   'build_internal_scripts_slave',