Start combining threads in system process.

This introduces four generic thread that services can
use in the system process:

- Background: part of the framework for all processes, for
work that is purely background (no timing constraint).
- UI: for time-critical display of UI.
- Foreground: normal foreground work.
- IO: performing IO operations.

I went through and moved services into these threads in the
places I felt relatively comfortable about understanding what
they are doing.  There are still a bunch more we need to look
at -- lots of networking stuff left, 3 or so different native
daemon connectors which I didn't know how much would block,
audio stuff, etc.

Also updated Watchdog to be aware of and check these new
threads, with a new API for other threads to also participate
in this checking.

Change-Id: Ie2f11061cebde5f018d7383b3a910fbbd11d5e11

1 files changed, 3 insertions, 7 deletions

diff --git a/services/java/com/android/server/usb/UsbDebuggingManager.java b/services/java/com/android/server/usb/UsbDebuggingManager.java
index 93d31144815f..ba3f1d1b6041 100644
--- a/services/java/com/android/server/usb/UsbDebuggingManager.java
+++ b/services/java/com/android/server/usb/UsbDebuggingManager.java
@@ -22,15 +22,14 @@ import android.content.Intent;
 import android.net.LocalSocket;
 import android.net.LocalSocketAddress;
 import android.os.Handler;
-import android.os.HandlerThread;
 import android.os.Environment;
 import android.os.FileUtils;
 import android.os.Looper;
 import android.os.Message;
-import android.os.Process;
 import android.os.SystemClock;
 import android.util.Slog;
 import android.util.Base64;
+import com.android.server.FgThread;
 
 import java.lang.Thread;
 import java.io.File;
@@ -54,7 +53,6 @@ public class UsbDebuggingManager implements Runnable {
 
     private final Context mContext;
     private final Handler mHandler;
-    private final HandlerThread mHandlerThread;
     private Thread mThread;
     private boolean mAdbEnabled = false;
     private String mFingerprints;
@@ -62,9 +60,7 @@ public class UsbDebuggingManager implements Runnable {
     private OutputStream mOutputStream = null;
 
     public UsbDebuggingManager(Context context) {
-        mHandlerThread = new HandlerThread("UsbDebuggingHandler");
-        mHandlerThread.start();
-        mHandler = new UsbDebuggingHandler(mHandlerThread.getLooper());
+        mHandler = new UsbDebuggingHandler(FgThread.get().getLooper());
         mContext = context;
     }
 
@@ -165,7 +161,7 @@ public class UsbDebuggingManager implements Runnable {
 
                     mAdbEnabled = true;
 
-                    mThread = new Thread(UsbDebuggingManager.this);
+                    mThread = new Thread(UsbDebuggingManager.this, "UsbDebuggingManager");
                     mThread.start();
 
                     break;