Remove unused policy proto messages.

Sync to the newest server-side version.

Bug: none
Change-Id: I5c93a8d5569e9079c1738014a632a63538136249
Reviewed-on: https://chromium-review.googlesource.com/1014110Reviewed-by: Julian Pastarmov <pastarmovj@chromium.org>
Commit-Queue: Pavol Marko <pmarko@chromium.org>
Cr-Commit-Position: refs/heads/master@{#551291}

components/policy/proto/device_management_backend.proto

@@ -844,31 +844,6 @@ message AppStatus {
   optional string required_platform_version = 5;
 }
 
-// The data about browser policies set and their sources.
-message BrowserPolicyData {
-  enum PolicySource {
-    UNKNOWN = 0;
-    // A machine level platform policy.
-    MACHINE_PLATFORM = 1;
-    // A user level platform policy.
-    USER_PLATFORM = 2;
-    // Machine level user cloud policy.
-    MACHINE_LEVEL_USER_CLOUD = 3;
-    // User level cloud policy.
-    USER_CLOUD = 4;
-  }
-  optional PolicySource source = 1;
-  optional string name = 2;
-  // TODO(b/68124101) maybe add policy value data.
-}
-
-// The data for an extension installed in the browser.
-message ExtensionData {
-  optional string extension_id = 1;  // required.
-  optional string version = 2;
-  repeated string permissions = 3;
-}
-
 // Chrome user profile level status.
 message ChromeUserProfileReport {
   // An string to uniquely identify this profile within the browser.