Dump PlatformCompat overrides to dumpsys

Dump info related to compat flags.

Test: adb shell am compat enable 42 foo.bar; \
	dumpsys platform_compat
Bug: 137183175
Change-Id: Ic429731a3364dab5902caeb12f48fecf2e49bb65
Merged-In: Ic429731a3364dab5902caeb12f48fecf2e49bb65

services/core/java/com/android/server/compat/CompatConfig.java

@@ -24,6 +24,7 @@ import android.util.LongSparseArray;
 import com.android.internal.annotations.GuardedBy;
 import com.android.internal.annotations.VisibleForTesting;
 
+import java.io.PrintWriter;
 /**
  * This class maintains state relating to platform compatibility changes.
  *
@@ -169,4 +170,22 @@ public final class CompatConfig {
         return overrideExists;
     }
 
+    /**
+    * Dumps the current list of compatibility config information.
+    *
+    * @param pw The {@link PrintWriter} instance to which the information will be dumped.
+    */
+    public void dumpConfig(PrintWriter pw) {
+        synchronized (mChanges) {
+            if (mChanges.size() == 0) {
+                pw.println("No compat overrides.");
+                return;
+            }
+            for (int i = 0; i < mChanges.size(); ++i) {
+                CompatChange c = mChanges.valueAt(i);
+                pw.println(c.toString());
+            }
+        }
+    }
+
 }

services/core/java/com/android/server/compat/PlatformCompat.java

@@ -56,6 +56,6 @@ public class PlatformCompat extends IPlatformCompat.Stub {
     @Override
     protected void dump(FileDescriptor fd, PrintWriter pw, String[] args) {
         if (!DumpUtils.checkDumpAndUsageStatsPermission(mContext, "platform_compat", pw)) return;
-        // TODO: Dump info about compatibility changes.
+        CompatConfig.get().dumpConfig(pw);
     }
 }