Fix #3037: implement pushClip/popClip on Android port

Ports/Android/src/com/codename1/impl/android/AndroidAsyncView.java

@@ -790,6 +790,45 @@ public String toString() {
             });
         }
 
+        private class SavedAsyncClip {
+            Rectangle clip;
+            Path clipP;
+            GeneralPath clipGP;
+            boolean clipIsPath;
+        }
+
+        private final java.util.ArrayDeque<SavedAsyncClip> savedClipStack =
+                new java.util.ArrayDeque<SavedAsyncClip>();
+
+        @Override
+        public void pushClip() {
+            SavedAsyncClip s = new SavedAsyncClip();
+            if (clip != null) {
+                s.clip = new Rectangle(clip);
+            }
+            if (clipP != null) {
+                s.clipP = new Path(clipP);
+            }
+            if (clipGP != null) {
+                s.clipGP = new GeneralPath(clipGP);
+            }
+            s.clipIsPath = clipIsPath;
+            savedClipStack.push(s);
+        }
+
+        @Override
+        public void popClip() {
+            if (savedClipStack.isEmpty()) {
+                return;
+            }
+            SavedAsyncClip s = savedClipStack.pop();
+            clip = s.clip;
+            clipP = s.clipP;
+            clipGP = s.clipGP;
+            clipIsPath = s.clipIsPath;
+            clipFresh = false;
+        }
+
 
         /*
         private Matrix getTransformMatrix(){

Ports/Android/src/com/codename1/impl/android/AndroidGraphics.java

@@ -1464,7 +1464,32 @@ public int getClipY() {
     }
 
     private boolean clipSet = false;
-
+
+    // Stack of clipSet values captured by pushClip. Each pushClip adds an
+    // unpaired canvas.save() so the clip can be widened (restored) on
+    // popClip. clipSet is reset to false after the push so that a setClip
+    // inside the push/pop block doesn't restore our pushed save.
+    private final java.util.ArrayDeque<Boolean> pushedClipSetStack = new java.util.ArrayDeque<Boolean>();
+
+    public void pushClip() {
+        canvas.save();
+        pushedClipSetStack.push(Boolean.valueOf(clipSet));
+        clipSet = false;
+    }
+
+    public void popClip() {
+        if (pushedClipSetStack.isEmpty()) {
+            return;
+        }
+        if (clipSet) {
+            canvas.restore();
+            clipSet = false;
+        }
+        canvas.restore();
+        clipSet = pushedClipSetStack.pop().booleanValue();
+        clipFresh = false;
+    }
+
     public void setClip(int x, int y, int width, int height) {
         //System.out.println("Setting clip  "+x+","+y+","+width+", "+height);
         if (clipSet) {

Ports/Android/src/com/codename1/impl/android/AndroidImplementation.java

@@ -5545,6 +5545,16 @@ public void rotate(Object nativeGraphics, float angle, int x, int y) {
         ((AndroidGraphics) nativeGraphics).rotate(angle, x, y);
     }
 
+    @Override
+    public void pushClip(Object graphics) {
+        ((AndroidGraphics) graphics).pushClip();
+    }
+
+    @Override
+    public void popClip(Object graphics) {
+        ((AndroidGraphics) graphics).popClip();
+    }
+
     @Override
     public boolean isTranslateMatrixSupported() {
         return true;