Stub out display manager service implementation.

Reverting to the previous stub as the display adapter registration
and the logical to physical mapping is not at all what we are going
to need moving forward.

Fixed up the service initialization order so that the display manager
service has a context from the start.

Change-Id: I717f2f1099c7a77180ef207c371ec8329258850a

2 files changed, 17 insertions, 2 deletions

diff --git a/core/java/android/app/ActivityThread.java b/core/java/android/app/ActivityThread.java
index 0438e77..2cdb086 100644
--- a/core/java/android/app/ActivityThread.java
+++ b/core/java/android/app/ActivityThread.java
@@ -1553,10 +1553,20 @@ public final class ActivityThread {
         if (dm != null && !forceUpdate) {
             return dm;
         }
+
+        DisplayManager displayManager = DisplayManager.getInstance();
+        if (displayManager == null) {
+            // may be null early in system startup
+            dm = new DisplayMetrics();
+            dm.setToDefaults();
+            return dm;
+        }
+
         if (dm == null) {
             dm = new DisplayMetrics();
             mDisplayMetrics.put(ci, dm);
         }
+
         CompatibilityInfoHolder cih = new CompatibilityInfoHolder();
         cih.set(ci);
         Display d = WindowManagerImpl.getDefault().makeCompatible(cih).getDefaultDisplay();
diff --git a/core/java/android/hardware/display/DisplayManager.java b/core/java/android/hardware/display/DisplayManager.java
index 640044b..dc79710 100644
--- a/core/java/android/hardware/display/DisplayManager.java
+++ b/core/java/android/hardware/display/DisplayManager.java
@@ -45,14 +45,19 @@ public final class DisplayManager {
 
     /**
      * Gets an instance of the display manager.
-     * @return The display manager instance.
+     *
+     * @return The display manager instance, may be null early in system startup
+     * before the display manager has been fully initialized.
+     *
      * @hide
      */
     public static DisplayManager getInstance() {
         synchronized (DisplayManager.class) {
             if (sInstance == null) {
                 IBinder b = ServiceManager.getService(Context.DISPLAY_SERVICE);
-                sInstance = new DisplayManager(IDisplayManager.Stub.asInterface(b));
+                if (b != null) {
+                    sInstance = new DisplayManager(IDisplayManager.Stub.asInterface(b));
+                }
             }
             return sInstance;
         }