Move zygote startup logic to the frameworks.

The Zygote class is now in com.android.internal.os. It is
responsible for the vast majority of work before and after
the call to fork(). It calls back into the Runtime via
the new dalvik.system.ZygoteHooks class to allow the Runtime
to perform pre fork cleanup and post fork initialization.

The native code in Zygote.cpp is a direct and straightforward
port of the existing code in art. Most differences are
superficial, for example :
- We use C style logging (ALOGE) instead of stream based
  logging.
- We call env->FatalError() instead of using LOG(FATAL)

Change-Id: Ia101fb2af12d23894fe57e4134d2bc6d142e5059
diff --git a/core/java/android/os/Process.java b/core/java/android/os/Process.java
index 631edd6..4cf8767 100644
--- a/core/java/android/os/Process.java
+++ b/core/java/android/os/Process.java
@@ -16,10 +16,11 @@
 
 package android.os;
 
-import android.net.LocalSocketAddress;
 import android.net.LocalSocket;
+import android.net.LocalSocketAddress;
 import android.util.Log;
-import dalvik.system.Zygote;
+
+import com.android.internal.os.Zygote;
 
 import java.io.BufferedWriter;
 import java.io.DataInputStream;