Kill the global references in the OpenGL wrappers.

Just use jniThrowException instead. Note that it would be trivial to throw
seemingly more appropriate exceptions (NullPointerException and
OutOfMemoryException in particular), but I'm only attempting to preserve
existing behavior here.

I also found shadowing bugs in some of the special-case functions, which
would previously always have leaked memory.

This also moves an accidental change to a generated file (ActivityThread ->
AppGlobals) into the generator, so it won't be overwritten in future.

Change-Id: Iab570310b568cb406c60dd0e2b8211f8a36ae590
diff --git a/opengl/tools/glgen/gen b/opengl/tools/glgen/gen
index 6c1a231..31f4190 100755
--- a/opengl/tools/glgen/gen
+++ b/opengl/tools/glgen/gen
@@ -21,7 +21,7 @@
 echo "package android.graphics;" > out/android/graphics/Canvas.java
 echo "public interface Canvas {}" >> out/android/graphics/Canvas.java
 
-echo "package android.app; import android.content.pm.IPackageManager; public class ActivityThread { public static final ActivityThread currentActivityThread() { return null; } public static final String currentPackageName(){ return null; } public static IPackageManager getPackageManager() { return null;} }" > out/android/app/ActivityThread.java
+echo "package android.app; import android.content.pm.IPackageManager; public class AppGlobals { public static IPackageManager getPackageManager() { return null;} }" > out/android/app/AppGlobals.java
 # echo "package android.content; import android.content.pm.PackageManager; public interface Context { public PackageManager getPackageManager(); }" > out/android/content/Context.java
 echo "package android.content.pm; public class ApplicationInfo {public int targetSdkVersion;}" > out/android/content/pm/ApplicationInfo.java
 echo "package android.content.pm; public interface IPackageManager {ApplicationInfo getApplicationInfo(java.lang.String packageName, int flags) throws android.os.RemoteException;}" > out/android/content/pm/IPackageManager.java