Revert of Remove DCHECK_IMPLIES/CHECK_IMPLIES.

components/tracing/child_memory_dump_manager_delegate_impl.h

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef COMPONENTS_TRACING_CHILD_MEMORY_DUMP_MANAGER_DELEGATE_IMPL_H_
 #define COMPONENTS_TRACING_CHILD_MEMORY_DUMP_MANAGER_DELEGATE_IMPL_H_
 
 #include "base/trace_event/memory_dump_manager.h"
 
 #include "base/memory/ref_counted.h"
@@ skipping 23 matching lines @@
   // base::trace_event::MemoryDumpManagerDelegate implementation.
   void RequestGlobalMemoryDump(
       const base::trace_event::MemoryDumpRequestArgs& args,
       const base::trace_event::MemoryDumpCallback& callback) override;
   uint64 GetTracingProcessId() const override;
 
   void SetChildTraceMessageFilter(ChildTraceMessageFilter* ctmf);
 
   // Pass kInvalidTracingProcessId to invalidate the id.
   void set_tracing_process_id(uint64 id) {
-    DCHECK(tracing_process_id_ ==
-               base::trace_event::MemoryDumpManager::kInvalidTracingProcessId ||
-           id ==
-               base::trace_event::MemoryDumpManager::kInvalidTracingProcessId ||
-           id == tracing_process_id_);
+    DCHECK_IMPLIES(
+        tracing_process_id_ !=
+            base::trace_event::MemoryDumpManager::kInvalidTracingProcessId,
+        id == base::trace_event::MemoryDumpManager::kInvalidTracingProcessId ||
+            id == tracing_process_id_);
     tracing_process_id_ = id;
   }
 
  protected:
   // Make CreateProcessDump() visible to ChildTraceMessageFilter.
   friend class ChildTraceMessageFilter;
 
  private:
   friend struct base::DefaultSingletonTraits<
       ChildMemoryDumpManagerDelegateImpl>;
@@ skipping 14 matching lines @@
   // The unique id of the child process, created for tracing and is expected to
   // be valid only when tracing is enabled.
   uint64 tracing_process_id_;
 
   DISALLOW_COPY_AND_ASSIGN(ChildMemoryDumpManagerDelegateImpl);
 };
 
 }  // namespace tracing
 
 #endif  // COMPONENTS_TRACING_CHILD_MEMORY_DUMP_MANAGER_DELEGATE_IMPL_H_