Reland: Remove DCHECK_IMPLIES/CHECK_IMPLIES.

content/renderer/input/input_handler_proxy.cc

Index: content/renderer/input/input_handler_proxy.cc
diff --git a/content/renderer/input/input_handler_proxy.cc b/content/renderer/input/input_handler_proxy.cc
index d4d3268078f160cb4cfad9e874c25116a96a5282..255492f0d4d2556ead2a4e7d15058fe7689ea0fe 100644
--- a/content/renderer/input/input_handler_proxy.cc
+++ b/content/renderer/input/input_handler_proxy.cc
@@ -757,8 +757,8 @@ void InputHandlerProxy::ExtendBoostedFlingTimeout(
 void InputHandlerProxy::Animate(base::TimeTicks time) {
   // If using synchronous animate, then only expect Animate attempts started by
   // the synchronous system. Don't let the InputHandler try to Animate also.
-  DCHECK_IMPLIES(input_handler_->IsCurrentlyScrollingInnerViewport(),
-                 allow_root_animate_);
+  DCHECK(!input_handler_->IsCurrentlyScrollingInnerViewport() ||
+         allow_root_animate_);
 
   if (scroll_elasticity_controller_)
     scroll_elasticity_controller_->Animate(time);