Ensure DEPS'd depot_tools auto update capability is disabled

Add hook to disable auto update of depot_tools. DEPS's repo should
remain at the revision sepecified in DEPS.

Bug: pdfium:1545
Change-Id: I5176cd51de76ca85157ae4c42fbbd6ec8eef9879
Reviewed-on: https://pdfium-review.googlesource.com/c/pdfium/+/70950
Reviewed-by: Lei Zhang <thestig@chromium.org>
Commit-Queue:  Ankit Kumar 🌪️ <ankk@microsoft.com>
diff --git a/DEPS b/DEPS
index ba210a5..3298448 100644
--- a/DEPS
+++ b/DEPS
@@ -220,6 +220,16 @@
 
 hooks = [
   {
+    # Ensure that the DEPS'd "depot_tools" has its self-update capability
+    # disabled.
+    'name': 'disable_depot_tools_selfupdate',
+    'pattern': '.',
+    'action': [ 'python',
+                'pdfium/third_party/depot_tools/update_depot_tools_toggle.py',
+                '--disable',
+    ],
+  },
+  {
     # Case-insensitivity for the Win SDK. Must run before win_toolchain below.
     'name': 'ciopfs_linux',
     'pattern': '.',