Download rc binaries for win cross-compile.

This copies code missing from the Chromium DEPS file.

Bug: angleproject:6170
Change-Id: I0f12fe185bf97e9d316a03bec57e4e3ce2fee080
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/3025126
Reviewed-by: Shahbaz Youssefi <syoussefi@chromium.org>
Commit-Queue: Jamie Madill <jmadill@chromium.org>
diff --git a/DEPS b/DEPS
index f32ae42..952cd35 100644
--- a/DEPS
+++ b/DEPS
@@ -3568,7 +3568,7 @@
   {
     'name': 'rc_win',
     'pattern': '.',
-    'condition': 'checkout_win and (host_os == "win" and not build_with_chromium)',
+    'condition': 'checkout_win and host_os == "win" and not build_with_chromium',
     'action': [ 'python',
                 'third_party/depot_tools/download_from_google_storage.py',
                 '--no_resume',
@@ -3579,6 +3579,31 @@
   },
 
   {
+    'name': 'rc_mac',
+    'pattern': '.',
+    'condition': 'checkout_win and host_os == "mac" and not build_with_chromium',
+    'action': [ 'python3',
+                'third_party/depot_tools/download_from_google_storage.py',
+                '--no_resume',
+                '--no_auth',
+                '--bucket', 'chromium-browser-clang/rc',
+                '-s', 'build/toolchain/win/rc/mac/rc.sha1',
+    ],
+  },
+  {
+    'name': 'rc_linux',
+    'pattern': '.',
+    'condition': 'checkout_win and host_os == "linux" and not build_with_chromium',
+    'action': [ 'python3',
+                'third_party/depot_tools/download_from_google_storage.py',
+                '--no_resume',
+                '--no_auth',
+                '--bucket', 'chromium-browser-clang/rc',
+                '-s', 'build/toolchain/win/rc/linux64/rc.sha1',
+    ]
+  },
+
+  {
     'name': 'fuchsia_sdk',
     'pattern': '.',
     'condition': 'checkout_fuchsia and not build_with_chromium',