Revert of infra_paths: keep cache paths super short to avoid long path issues (patchset #1 id:1 of https://codereview.chromium.org/2102613002/ )

Reason for revert:
/b/cache dir on slaves were not cleaned up and now disk alerts are firing

please come up with a cleanup strategy before re-landing this CL

Original issue's description:
> infra_paths: keep cache paths super short to avoid long path issues
>
> BUG=623575
>
> Committed: aa0b3b6bd0

TBR=emso@chromium.org,sergiyb@chromium.org,tandrii@chromium.org,thakis@chromium.org,phajdan.jr@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=623575

Review-Url: https://codereview.chromium.org/2100793004

recipe_modules/infra_paths/path_config.py

@@ -36,18 +36,16 @@ def infra_kitchen(c):
     b_dir = b_dir[:-1]
 
   if c.PLATFORM in ('linux', 'mac'):
-    c.base_paths['cache'] = ('/', 'b', 'c')
-    c.base_paths['builder_cache'] = c.base_paths['cache'] + ('b',)
-    for path in ('git_cache', 'goma_cache', 'goma_deps_cache'):
+    c.base_paths['cache'] = (
+        '/', 'b', 'cache', 'chromium')
+    for path in ('builder_cache', 'git_cache', 'goma_cache', 'goma_deps_cache'):
       c.base_paths[path] = c.base_paths['cache'] + (path,)
   elif b_dir:
-    c.base_paths['cache'] = b_dir + ('c',)
-    c.base_paths['builder_cache'] = c.base_paths['cache'] + ('b',)
-    for path in ('git_cache', 'goma_cache', 'goma_deps_cache'):
+    c.base_paths['cache'] = b_dir + ('cache', 'chromium')
+    for path in ('builder_cache', 'git_cache', 'goma_cache', 'goma_deps_cache'):
       c.base_paths[path] = c.base_paths['cache'] + (path,)
   else:  # pragma: no cover
-    c.base_paths['cache'] = c.base_paths['root'] + ('c',)
-    c.base_paths['builder_cache'] = c.base_paths['cache'] + ('b',)
+    c.base_paths['cache'] = c.base_paths['root'] + ('cache',)
     c.base_paths['git_cache'] = c.base_paths['root'] + ('cache_dir',)
-    for path in ('goma_cache', 'goma_deps_cache'):
+    for path in ('builder_cache', 'goma_cache', 'goma_deps_cache'):
       c.base_paths[path] = c.base_paths['cache'] + (path,)