Explain what a DPC is in new API docs.

Fixes: 218876435

Test: N/A
Change-Id: I2e7ee6f1f46f9e672f4707740585cda79c2d1542

core/java/android/app/admin/DevicePolicyManager.java

@@ -15606,7 +15606,9 @@ public class DevicePolicyManager {
     }
 
     /**
-     * Returns a boolean for whether the DPC has been downloaded during provisioning.
+     * Returns a boolean for whether the DPC
+     * (Device Policy Controller, the agent responsible for enforcing policy)
+     * has been downloaded during provisioning.
      *
      * <p>If true is returned, then any attempts to begin setup again should result in factory reset
      *
@@ -15627,9 +15629,11 @@ public class DevicePolicyManager {
     }
 
     /**
-     * Use to indicate that the DPC has or has not been downloaded during provisioning.
+     * Indicates that the DPC (Device Policy Controller, the agent responsible for enforcing policy)
+     * has or has not been downloaded during provisioning.
      *
-     * @param downloaded {@code true} if the dpc has been downloaded during provisioning. false otherwise.
+     * @param downloaded {@code true} if the dpc has been downloaded during provisioning.
+     *                               {@code false} otherwise.
      *
      * @hide
      */