Layoutlib tests now check methods return value [DO NOT MERGE]

The change is a cherry-pick of relevant fixes from the following
commits on master branch:
the followning commits:
9be03c4e980d3058aeb3fd730da5f7d4a4a4f8a8 and
e05bb956ce429618fd4f971a9dc708b9313c59ea

Change-Id: I87cef323c4eaee4e9f60475f01156b276593fa50

3 files changed, 15 insertions, 5 deletions

diff --git a/tools/layoutlib/bridge/src/android/graphics/Bitmap_Delegate.java b/tools/layoutlib/bridge/src/android/graphics/Bitmap_Delegate.java
index 13d2ba1..f74e4d1 100644
--- a/tools/layoutlib/bridge/src/android/graphics/Bitmap_Delegate.java
+++ b/tools/layoutlib/bridge/src/android/graphics/Bitmap_Delegate.java
@@ -518,7 +518,8 @@ public final class Bitmap_Delegate {
     }
 
     @LayoutlibDelegate
-    /*package*/ static void nativeSetHasAlpha(int nativeBitmap, boolean hasAlpha) {
+    /*package*/ static void nativeSetAlphaAndPremultiplied(int nativeBitmap, boolean hasAlpha,
+            boolean isPremul) {
         // get the delegate from the native int.
         Bitmap_Delegate delegate = sManager.getDelegate(nativeBitmap);
         if (delegate == null) {
diff --git a/tools/layoutlib/bridge/src/android/graphics/Region_Delegate.java b/tools/layoutlib/bridge/src/android/graphics/Region_Delegate.java
index cb31b8f..57af6e9 100644
--- a/tools/layoutlib/bridge/src/android/graphics/Region_Delegate.java
+++ b/tools/layoutlib/bridge/src/android/graphics/Region_Delegate.java
@@ -275,21 +275,21 @@ public class Region_Delegate {
     }
 
     @LayoutlibDelegate
-    /*package*/ static boolean nativeSetRegion(int native_dst, int native_src) {
+    /*package*/ static void nativeSetRegion(int native_dst, int native_src) {
         Region_Delegate dstRegion = sManager.getDelegate(native_dst);
         if (dstRegion == null) {
-            return true;
+            return;
         }
 
         Region_Delegate srcRegion = sManager.getDelegate(native_src);
         if (srcRegion == null) {
-            return true;
+            return;
         }
 
         dstRegion.mArea.reset();
         dstRegion.mArea.add(srcRegion.mArea);
 
-        return true;
+        return;
     }
 
     @LayoutlibDelegate
diff --git a/tools/layoutlib/bridge/tests/src/com/android/layoutlib/bridge/TestDelegates.java b/tools/layoutlib/bridge/tests/src/com/android/layoutlib/bridge/TestDelegates.java
index d3218db..7c0bc84 100644
--- a/tools/layoutlib/bridge/tests/src/com/android/layoutlib/bridge/TestDelegates.java
+++ b/tools/layoutlib/bridge/tests/src/com/android/layoutlib/bridge/TestDelegates.java
@@ -129,6 +129,15 @@ public class TestDelegates extends TestCase {
                                 originalClass.getName()),
                         delegateMethod.getAnnotation(LayoutlibDelegate.class));
 
+                // check the return type of the methods match.
+                assertTrue(
+                        String.format("Delegate method %1$s.%2$s does not match the corresponding " +
+                                "framework method which returns %3$s",
+                                delegateClass.getName(),
+                                getMethodName(delegateMethod),
+                                originalMethod.getReturnType().getName()),
+                        delegateMethod.getReturnType() == originalMethod.getReturnType());
+
                 // check that the method is static
                 assertTrue(
                         String.format(