Remove deprecated base::Bind APIs (see issue #3140)

This CL removes the following deprecated APIs:

- base::Bind()
- base::Callback
- base::Closure
- base::CancelableCallback
- base::CancelableClosure

The behavior that these APIs provided is still available using the *Repeating*
variants. However, consider strongly whether using these variants is actually
necessary in your case or whether the *Once* variants will suffice: unless your
callback *objects* (note: not variables!) need to be called multiple times,
they most likely can and should be the Once variants.

This applies the same changes as https://crrev.com/6cc94b5339.

include/base/cef_bind.h

@@ -54,9 +54,6 @@
 //   auto cb = base::BindOnce(&C::F, instance);
 //   std::move(cb).Run();  // Identical to instance->F()
 //
-// base::Bind is currently a type alias for base::BindRepeating(). In the
-// future, we expect to flip this to default to base::BindOnce().
-//
 // See //docs/callback.md for the full documentation.
 //
 // -----------------------------------------------------------------------------
@@ -126,17 +123,6 @@ BindRepeating(Functor&& functor, Args&&... args) {
                                                std::forward<Args>(args)...);
 }
 
-// Unannotated Bind.
-// TODO(tzik): Deprecate this and migrate to OnceCallback and
-// RepeatingCallback, once they get ready.
-template <typename Functor, typename... Args>
-inline Callback<internal::MakeUnboundRunType<Functor, Args...>> Bind(
-    Functor&& functor,
-    Args&&... args) {
-  return base::BindRepeating(std::forward<Functor>(functor),
-                             std::forward<Args>(args)...);
-}
-
 // Special cases for binding to a base::Callback without extra bound arguments.
 // We CHECK() the validity of callback to guard against null pointers
 // accidentally ending up in posted tasks, causing hard-to-debug crashes.
@@ -159,12 +145,6 @@ RepeatingCallback<Signature> BindRepeating(
   return callback;
 }
 
-template <typename Signature>
-Callback<Signature> Bind(Callback<Signature> callback) {
-  CHECK(callback);
-  return callback;
-}
-
 // Unretained() allows binding a non-refcounted class, and to disable
 // refcounting on arguments that are refcounted objects.
 //

include/base/cef_callback.h

@@ -60,9 +60,6 @@
 // will be a no-op. Note that |IsCancelled()| and |is_null()| are distinct:
 // simply cancelling a callback will not also make it null.
 //
-// base::Callback is currently a type alias for base::RepeatingCallback. In the
-// future, we expect to flip this to default to base::OnceCallback.
-//
 // See https://chromium.googlesource.com/chromium/src/+/HEAD/docs/callback.md
 // for the full documentation.
 
@@ -115,7 +112,7 @@ class OnceCallback<R(Args...)> : public internal::CallbackBase {
     return *this;
   }
 
-  R Run(Args... args) const & {
+  R Run(Args... args) const& {
     static_assert(!sizeof(*this),
                   "OnceCallback::Run() may only be invoked on a non-const "
                   "rvalue, i.e. std::move(callback).Run().");
@@ -195,7 +192,7 @@ class RepeatingCallback<R(Args...)> : public internal::CallbackBaseCopyable {
     return !operator==(other);
   }
 
-  R Run(Args... args) const & {
+  R Run(Args... args) const& {
     PolymorphicInvoke f =
         reinterpret_cast<PolymorphicInvoke>(this->polymorphic_invoke());
     return f(this->bind_state_.get(), std::forward<Args>(args)...);

include/base/cef_callback_forward.h

@@ -48,15 +48,11 @@ class OnceCallback;
 template <typename Signature>
 class RepeatingCallback;
 
-template <typename Signature>
-using Callback = RepeatingCallback<Signature>;
-
 // Syntactic sugar to make OnceClosure<void()> and RepeatingClosure<void()>
 // easier to declare since they will be used in a lot of APIs with delayed
 // execution.
 using OnceClosure = OnceCallback<void()>;
 using RepeatingClosure = RepeatingCallback<void()>;
-using Closure = Callback<void()>;
 
 }  // namespace base
 

include/base/cef_cancelable_callback.h

@@ -83,10 +83,10 @@
 
 #include "include/base/cef_bind.h"
 #include "include/base/cef_callback.h"
-#include "include/base/internal/cef_callback_internal.h"
-#include "include/base/cef_logging.h"
 #include "include/base/cef_compiler_specific.h"
+#include "include/base/cef_logging.h"
 #include "include/base/cef_weak_ptr.h"
+#include "include/base/internal/cef_callback_internal.h"
 
 namespace base {
 namespace internal {
@@ -113,9 +113,7 @@ class CancelableCallbackImpl {
   }
 
   // Returns true if the wrapped callback has been cancelled.
-  bool IsCancelled() const {
+  bool IsCancelled() const { return callback_.is_null(); }
-    return callback_.is_null();
-  }
 
   // Sets |callback| as the closure that may be cancelled. |callback| may not
   // be null. Outstanding and any previously wrapped callbacks are cancelled.
@@ -180,10 +178,6 @@ using CancelableRepeatingCallback =
     internal::CancelableCallbackImpl<RepeatingCallback<Signature>>;
 using CancelableRepeatingClosure = CancelableRepeatingCallback<void()>;
 
-template <typename Signature>
-using CancelableCallback = CancelableRepeatingCallback<Signature>;
-using CancelableClosure = CancelableCallback<void()>;
-
 }  // namespace base
 
 #endif  // !USING_CHROMIUM_INCLUDES