Replace safe-bool idiom with explicit WeakPtr::operator bool()

base/memory/weak_ptr_unittest.cc

Index: base/memory/weak_ptr_unittest.cc
diff --git a/base/memory/weak_ptr_unittest.cc b/base/memory/weak_ptr_unittest.cc
index 2eb6d295780f4b43d18338c0c48a5b34e9364e6a..eb3a4b249c140528bc7168c4dff6bdf806d4317f 100644
--- a/base/memory/weak_ptr_unittest.cc
+++ b/base/memory/weak_ptr_unittest.cc
@@ -308,6 +308,19 @@ TEST(WeakPtrFactoryTest, BooleanTesting) {
   }
 }
 
+TEST(WeakPtrFactoryTest, ComparisonToNull) {
+  int data;
+  WeakPtrFactory<int> factory(&data);
+
+  WeakPtr<int> ptr_to_an_instance = factory.GetWeakPtr();
+  EXPECT_NE(nullptr, ptr_to_an_instance);
+  EXPECT_NE(ptr_to_an_instance, nullptr);
+
+  WeakPtr<int> null_ptr;
+  EXPECT_EQ(null_ptr, nullptr);
+  EXPECT_EQ(nullptr, null_ptr);
+}
+
 TEST(WeakPtrTest, InvalidateWeakPtrs) {
   int data;
   WeakPtrFactory<int> factory(&data);