Fix several small logging issues.

This includes:
1) invert HIDE_STACK_CRAWLS to SHOW_STACK_CRAWLS so it's immediately
clear from the config file that something is enabled (if anything is
true).
2) Merge stack collection code into a method, so we can remove the
repeated code.
3) Remove copying of some constants in AppTransition and just import
them directly.

Change-Id: I3190ee0a5963720ac6285b4f48b2705e84f04ab5
diff --git a/services/core/java/com/android/server/wm/AppTransition.java b/services/core/java/com/android/server/wm/AppTransition.java
index a7a4ed1..0622fad 100644
--- a/services/core/java/com/android/server/wm/AppTransition.java
+++ b/services/core/java/com/android/server/wm/AppTransition.java
@@ -39,6 +39,8 @@
 import static com.android.internal.R.styleable.WindowAnimation_wallpaperIntraOpenExitAnimation;
 import static com.android.internal.R.styleable.WindowAnimation_wallpaperOpenEnterAnimation;
 import static com.android.internal.R.styleable.WindowAnimation_wallpaperOpenExitAnimation;
+import static com.android.server.wm.WindowManagerDebugConfig.DEBUG_ANIM;
+import static com.android.server.wm.WindowManagerDebugConfig.DEBUG_APP_TRANSITIONS;
 import static com.android.server.wm.WindowManagerDebugConfig.TAG_WITH_CLASS_NAME;
 import static com.android.server.wm.WindowManagerDebugConfig.TAG_WM;
 
@@ -85,9 +87,6 @@
 // made visible or hidden at the next transition.
 public class AppTransition implements Dump {
     private static final String TAG = TAG_WITH_CLASS_NAME ? "AppTransition" : TAG_WM;
-    private static final boolean DEBUG_APP_TRANSITIONS =
-            WindowManagerDebugConfig.DEBUG_APP_TRANSITIONS;
-    private static final boolean DEBUG_ANIM = WindowManagerDebugConfig.DEBUG_ANIM;
     private static final int CLIP_REVEAL_TRANSLATION_Y_DP = 8;
 
     /** Not set up for a transition. */