cmsdk: Mandate performance feature xml's for service implementation.

The feature xml plays two roles:

      1) To allow sdk interface (constructor) to throw when system
      service is unavailable. This allows for clearer platform
      development debugging.

      2) To allow for simpler disambiguation of what services to
      instrument in a modular environment.

Change-Id: I50f5993ff9c5107fdeaa9a5aa95377235eb3ac02
TICKET: CYNGNOS-2294

cm/lib/main/java/org/cyanogenmod/platform/internal/PerformanceManagerService.java

@@ -29,6 +29,7 @@ import android.os.Message;
 import android.os.Process;
 import android.os.SystemProperties;
 import android.text.TextUtils;
+import android.util.Log;
 import android.util.Slog;
 
 import com.android.server.ServiceThread;
@@ -110,7 +111,13 @@ public class PerformanceManagerService extends SystemService {
 
     @Override
     public void onStart() {
-        publishBinderService(CMContextConstants.CM_PERFORMANCE_SERVICE, mBinder);
+        if (mContext.getPackageManager().hasSystemFeature(
+                CMContextConstants.Features.PERFORMANCE)) {
+            publishBinderService(CMContextConstants.CM_PERFORMANCE_SERVICE, mBinder);
+        } else {
+            Log.wtf(TAG, "CM performance service started by system server but feature xml not" +
+                    " declared. Not publishing binder service!");
+        }
         publishLocalService(PerformanceManagerInternal.class, new LocalService());
     }
 

src/java/cyanogenmod/app/CMContextConstants.java

@@ -165,5 +165,13 @@ public final class CMContextConstants {
          */
         @SdkConstant(SdkConstant.SdkConstantType.FEATURE)
         public static final String THEMES = "org.cyanogenmod.theme";
+
+        /**
+         * Feature for {@link PackageManager#getSystemAvailableFeatures} and
+         * {@link PackageManager#hasSystemFeature}: The device includes the cm performance service
+         * utilized by the cmsdk.
+         */
+        @SdkConstant(SdkConstant.SdkConstantType.FEATURE)
+        public static final String PERFORMANCE = "org.cyanogenmod.performance";
     }
 }

src/java/cyanogenmod/power/PerformanceManager.java

@@ -78,7 +78,12 @@ public class PerformanceManager {
 
     private PerformanceManager(Context context) {
         sService = getService();
-
+        if (context.getPackageManager().hasSystemFeature(
+                CMContextConstants.Features.PERFORMANCE) && sService == null) {
+            throw new RuntimeException("Unable to get PerformanceManagerService. The service" +
+                    " either crashed, was not started, or the interface has been called to early" +
+                    " in SystemServer init");
+        }
         try {
             if (sService != null) {
                 mNumberOfProfiles = sService.getNumberOfProfiles();

tests/src/org/cyanogenmod/tests/power/unit/PerfomanceManagerTest.java

@@ -17,6 +17,8 @@ package org.cyanogenmod.tests.power.unit;
 
 import android.test.AndroidTestCase;
 import android.test.suitebuilder.annotation.SmallTest;
+
+import cyanogenmod.app.CMContextConstants;
 import cyanogenmod.power.IPerformanceManager;
 import cyanogenmod.power.PerformanceManager;
 
@@ -34,6 +36,9 @@ public class PerfomanceManagerTest extends AndroidTestCase {
     @Override
     protected void setUp() throws Exception {
         super.setUp();
+        // Only run this if we support performance abstraction
+        org.junit.Assume.assumeTrue(mContext.getPackageManager().hasSystemFeature(
+                CMContextConstants.Features.PERFORMANCE));
         mCMPerformanceManager = PerformanceManager.getInstance(mContext);
         // Save the perf profile for later restore.
         mSavedPerfProfile = mCMPerformanceManager.getPowerProfile();