Update schema for PolicyRefreshRate and MaxInvalidationFetchDelay

Include the min and max values already specified in the policy
descriptions and in the code handling the policies.

The limits for the PolicyRefreshRate policy are specified in
components/policy/core/common/cloud/cloud_policy_refresh_scheduler.cc.

The limits for the MaxInvalidationFetchDelay policy are specified in
chrome/browser/policy/cloud/cloud_policy_invalidator.cc.

BYPASS_POLICY_COMPATIBILITY_CHECK=Min and max values already specified,
                                  they just were missing from the schema

Change-Id: Ia1b3904dd1f377d5bc1ee7c2742f3eaeb3f34969
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2349211
Commit-Queue: Chris Sharp <csharp@chromium.org>
Reviewed-by: Pavol Marko <pmarko@chromium.org>
Cr-Commit-Position: refs/heads/master@{#797407}

components/policy/resources/policy_templates.json

@@ -6881,7 +6881,7 @@
       'name': 'PolicyRefreshRate',
       'owners': ['file://components/policy/resources/OWNERS'],
       'type': 'int',
-      'schema': { 'type': 'integer' },
+      'schema': { 'type': 'integer', 'minimum': 1800000, 'maximum': 86400000 },
       'supported_on': ['chrome_os:11-', 'chrome.*:79-'],
       'features': {
         'dynamic_refresh': True,
@@ -6903,7 +6903,7 @@
       'name': 'MaxInvalidationFetchDelay',
       'owners': ['stepco@chromium.org', 'poromov@chromium.org'],
       'type': 'int',
-      'schema': { 'type': 'integer' },
+      'schema': { 'type': 'integer', 'minimum': 1000, 'maximum': 30000 },
       'supported_on': ['chrome.*:30-', 'chrome_os:30-'],
       'features': {
         'dynamic_refresh': True,