Remove use_relative_hooks now that all deprecated uses are removed.

Bug: chromium:1107325
Change-Id: Iac1ff8ef9426c8f57b6e12783de0ffbb0625ef2b
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/2349170
Reviewed-by: Josip Sokcevic <sokcevic@google.com>
Commit-Queue: Corentin Wallez <cwallez@chromium.org>

gclient.py

@@ -793,10 +793,6 @@ class Dependency(gclient_utils.WorkItem, DependencySettings):
         self._postprocess_deps(deps, rel_prefix), self._use_relative_paths)
 
     # compute which working directory should be used for hooks
-    if local_scope.get('use_relative_hooks', False):
-      print('use_relative_hooks is deprecated, please remove it from DEPS. ' +
-            '(it was merged in use_relative_paths)', file=sys.stderr)
-
     hooks_cwd = self.root.root_dir
     if self._use_relative_paths:
       hooks_cwd = os.path.join(hooks_cwd, self.name)

gclient_eval.py

@@ -235,10 +235,6 @@ _GCLIENT_SCHEMA = schema.Schema(
         # file.
         schema.Optional('use_relative_paths'): bool,
 
-        # For recursed-upon sub-dependencies, run their hooks relative to the
-        # parent's path instead of relative to the .gclient file.
-        schema.Optional('use_relative_hooks'): bool,
-
         # Variables that can be referenced using Var() - see 'deps'.
         schema.Optional('vars'): _NodeDictSchema({
             schema.Optional(basestring): schema.Or(ConstantString,