Clean up final uses of scoped_ptr<T>::PassAs() and remove it.

This helper to upcast in return statements is no longer needed.

BUG=423621

Review URL: https://codereview.chromium.org/663243003

Cr-Commit-Position: refs/heads/master@{#300548}

base/memory/scoped_ptr.h

@@ -73,16 +73,6 @@
 //
 //   scoped_ptr<Foo> foo(new Foo());
 //   scoped_ptr<FooParent> parent(foo.Pass());
-//
-// PassAs<>() should be used to upcast return value in return statement:
-//
-//   scoped_ptr<Foo> CreateFoo() {
-//     scoped_ptr<FooChild> result(new FooChild());
-//     return result.PassAs<Foo>();
-//   }
-//
-// Note that PassAs<>() is implemented only for scoped_ptr<T>, but not for
-// scoped_ptr<T[]>. This is because casting array pointers may not be safe.
 
 #ifndef BASE_MEMORY_SCOPED_PTR_H_
 #define BASE_MEMORY_SCOPED_PTR_H_
@@ -436,17 +426,6 @@ class scoped_ptr {
     return impl_.release();
   }
 
-  // C++98 doesn't support functions templates with default parameters which
-  // makes it hard to write a PassAs() that understands converting the deleter
-  // while preserving simple calling semantics.
-  //
-  // Until there is a use case for PassAs() with custom deleters, just ignore
-  // the custom deleter.
-  template <typename PassAsType>
-  scoped_ptr<PassAsType> PassAs() {
-    return scoped_ptr<PassAsType>(Pass());
-  }
-
  private:
   // Needed to reach into |impl_| in the constructor.
   template <typename U, typename V> friend class scoped_ptr;

base/memory/scoped_ptr_unittest.cc

@@ -94,11 +94,6 @@ scoped_ptr<ConDecLogger> TestReturnOfType(int* constructed) {
   return scoped_ptr<ConDecLogger>(new ConDecLogger(constructed));
 }
 
-scoped_ptr<ConDecLoggerParent> UpcastUsingPassAs(
-    scoped_ptr<ConDecLogger> object) {
-  return object.PassAs<ConDecLoggerParent>();
-}
-
 }  // namespace
 
 TEST(ScopedPtrTest, ScopedPtr) {
@@ -462,22 +457,6 @@ TEST(ScopedPtrTest, ReturnTypeBehavior) {
   EXPECT_EQ(0, constructed);
 }
 
-TEST(ScopedPtrTest, PassAs) {
-  int constructed = 0;
-  {
-    scoped_ptr<ConDecLogger> scoper(new ConDecLogger(&constructed));
-    EXPECT_EQ(1, constructed);
-    EXPECT_TRUE(scoper.get());
-
-    scoped_ptr<ConDecLoggerParent> scoper_parent;
-    scoper_parent = UpcastUsingPassAs(scoper.Pass());
-    EXPECT_EQ(1, constructed);
-    EXPECT_TRUE(scoper_parent.get());
-    EXPECT_FALSE(scoper.get());
-  }
-  EXPECT_EQ(0, constructed);
-}
-
 TEST(ScopedPtrTest, CustomDeleter) {
   double dummy_value;  // Custom deleter never touches this value.
   int deletes = 0;

cc/PRESUBMIT.py

@@ -191,12 +191,6 @@ def CheckScopedPtr(input_api, output_api,
         errors.append(output_api.PresubmitError(
           '%s:%d uses scoped_ptr<T>(). Use nullptr instead.' %
           (f.LocalPath(), line_number)))
-      # Disallow:
-      # foo.PassAs<T>();
-      if re.search(r'\bPassAs<.*?>\(\)', line):
-        errors.append(output_api.PresubmitError(
-          '%s:%d uses PassAs<T>(). Use Pass() instead.' %
-          (f.LocalPath(), line_number)))
   return errors
 
 def FindUnquotedQuote(contents, pos):

net/socket/ssl_client_socket_unittest.cc

@@ -1822,7 +1822,7 @@ TEST_F(SSLClientSocketTest, Connect_WithZeroReturn) {
 
   SynchronousErrorStreamSocket* raw_transport = transport.get();
   scoped_ptr<SSLClientSocket> sock(
-      CreateSSLClientSocket(transport.PassAs<StreamSocket>(),
+      CreateSSLClientSocket(transport.Pass(),
                             test_server.host_port_pair(),
                             kDefaultSSLConfig));
 
@@ -1859,7 +1859,7 @@ TEST_F(SSLClientSocketTest, Read_WithZeroReturn) {
 
   SynchronousErrorStreamSocket* raw_transport = transport.get();
   scoped_ptr<SSLClientSocket> sock(
-      CreateSSLClientSocket(transport.PassAs<StreamSocket>(),
+      CreateSSLClientSocket(transport.Pass(),
                             test_server.host_port_pair(),
                             ssl_config));