add bunch of new java APIs: mostly stubs or copied from AOSP

Many of these classes are only needed to be subclassed by androidx
support library, which is used in many android apps

src/api-impl/android/animation/Animator.java

@@ -0,0 +1,9 @@
+package android.animation;
+
+public class Animator {
+
+	public void setTarget(Object target) {}
+
+	public void start() {}
+	
+}

src/api-impl/android/animation/AnimatorInflater.java

@@ -0,0 +1,11 @@
+package android.animation;
+
+import android.content.Context;
+
+public class AnimatorInflater {
+
+	public static Animator loadAnimator(Context context, int resId) {
+		return new Animator();
+	}
+	
+}

src/api-impl/android/animation/AnimatorListenerAdapter.java

@@ -0,0 +1,56 @@
+/*
+ * Copyright (C) 2010 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.animation;
+
+/**
+ * This adapter class provides empty implementations of the methods from {@link android.animation.Animator.AnimatorListener}.
+ * Any custom listener that cares only about a subset of the methods of this listener can
+ * simply subclass this adapter class instead of implementing the interface directly.
+ */
+public abstract class AnimatorListenerAdapter /*implements Animator.AnimatorListener,
+		Animator.AnimatorPauseListener*/ {
+	/**
+	 * {@inheritDoc}
+	 */
+	public void onAnimationCancel(Animator animation) {
+	}
+	/**
+	 * {@inheritDoc}
+	 */
+	public void onAnimationEnd(Animator animation) {
+	}
+	/**
+	 * {@inheritDoc}
+	 */
+	public void onAnimationRepeat(Animator animation) {
+	}
+	/**
+	 * {@inheritDoc}
+	 */
+	public void onAnimationStart(Animator animation) {
+	}
+	/**
+	 * {@inheritDoc}
+	 */
+	public void onAnimationPause(Animator animation) {
+	}
+	/**
+	 * {@inheritDoc}
+	 */
+	public void onAnimationResume(Animator animation) {
+	}
+}

src/api-impl/android/animation/LayoutTransition.java

@@ -0,0 +1,5 @@
+package android.animation;
+
+public class LayoutTransition {
+	
+}

src/api-impl/android/animation/ValueAnimator.java

@@ -0,0 +1,33 @@
+package android.animation;
+
+public class ValueAnimator {
+
+	public static ValueAnimator ofFloat(float... values) {
+		return new ValueAnimator();
+	}
+
+	public ValueAnimator setDuration(long duration) {
+		return this;
+	}
+
+	public void addUpdateListener(AnimatorUpdateListener listener) {}
+
+	public static long getFrameDelay() {
+		return 20; // 20ms frame interval
+	}
+
+	/**
+	 * Implementors of this interface can add themselves as update listeners
+	 * to an <code>ValueAnimator</code> instance to receive callbacks on every animation
+	 * frame, after the current frame's values have been calculated for that
+	 * <code>ValueAnimator</code>.
+	 */
+	public static interface AnimatorUpdateListener {
+		/**
+		 * <p>Notifies the occurrence of another frame of the animation.</p>
+		 *
+		 * @param animation The animation which was repeated.
+		 */
+		void onAnimationUpdate(ValueAnimator animation);
+	}
+}