Merge changes I66c97386,Id205c88d

* changes:
  libutils: wp::fromExisting bugfix
  libutils: add sp::cast method
diff --git a/libutils/RefBase_test.cpp b/libutils/RefBase_test.cpp
index dcc469e..93f9654 100644
--- a/libutils/RefBase_test.cpp
+++ b/libutils/RefBase_test.cpp
@@ -242,12 +242,12 @@
 }
 
 TEST(RefBase, AssertWeakRefExistsSuccess) {
-    // uses some other refcounting method, or non at all
     bool isDeleted;
     sp<Foo> foo = sp<Foo>::make(&isDeleted);
     wp<Foo> weakFoo = foo;
 
     EXPECT_EQ(weakFoo, wp<Foo>::fromExisting(foo.get()));
+    EXPECT_EQ(weakFoo.unsafe_get(), wp<Foo>::fromExisting(foo.get()).unsafe_get());
 
     EXPECT_FALSE(isDeleted);
     foo = nullptr;
@@ -255,7 +255,7 @@
 }
 
 TEST(RefBase, AssertWeakRefExistsDeath) {
-    // uses some other refcounting method, or non at all
+    // uses some other refcounting method, or none at all
     bool isDeleted;
     Foo* foo = new Foo(&isDeleted);
 
diff --git a/libutils/include/utils/RefBase.h b/libutils/include/utils/RefBase.h
index 5a5bd56..7148949 100644
--- a/libutils/include/utils/RefBase.h
+++ b/libutils/include/utils/RefBase.h
@@ -547,6 +547,7 @@
     refs->incWeakRequireWeak(other);
 
     wp<T> ret;
+    ret.m_ptr = other;
     ret.m_refs = refs;
     return ret;
 }
diff --git a/libutils/include/utils/StrongPointer.h b/libutils/include/utils/StrongPointer.h
index 1f07052..dd53b9e 100644
--- a/libutils/include/utils/StrongPointer.h
+++ b/libutils/include/utils/StrongPointer.h
@@ -72,6 +72,12 @@
     template<typename U> sp(const sp<U>& other);  // NOLINT(implicit)
     template<typename U> sp(sp<U>&& other);  // NOLINT(implicit)
 
+    // Cast a strong pointer directly from one type to another. Constructors
+    // allow changing types, but only if they are pointer-compatible. This does
+    // a static_cast internally.
+    template <typename U>
+    static inline sp<T> cast(const sp<U>& other);
+
     ~sp();
 
     // Assignment
@@ -279,6 +285,12 @@
     other.m_ptr = nullptr;
 }
 
+template <typename T>
+template <typename U>
+sp<T> sp<T>::cast(const sp<U>& other) {
+    return sp<T>::fromExisting(static_cast<T*>(other.get()));
+}
+
 template<typename T>
 sp<T>::~sp() {
     if (m_ptr)