In the .mm files use the crashpad::implicit_cast .. explicitly.

util/mac/launchd.mm

 // Copyright 2014 The Crashpad Authors. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
 // You may obtain a copy of the License at
 //
 //     http://www.apache.org/licenses/LICENSE-2.0
 //
 // Unless required by applicable law or agreed to in writing, software
 // distributed under the License is distributed on an "AS IS" BASIS,
 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
 #include "util/mac/launchd.h"
 
 #import <Foundation/Foundation.h>
 
 #include "base/basictypes.h"

[Mark Mentovai, 2015/09/14 22:10:01]

This #include isn’t needed anymore.

 #include "base/mac/foundation_util.h"
 #include "base/mac/scoped_launch_data.h"
 #include "base/mac/scoped_cftyperef.h"
 #include "base/strings/sys_string_conversions.h"
 #include "util/misc/implicit_cast.h"
 
 namespace crashpad {
 
 launch_data_t CFPropertyToLaunchData(CFPropertyListRef property_cf) {
   @autoreleasepool {
     // This function mixes Foundation and Core Foundation access to property
     // list elements according to which is more convenient and correct for any
     // specific task.
 
     launch_data_t data_launch = nullptr;
     CFTypeID type_id_cf = CFGetTypeID(property_cf);
 
     if (type_id_cf == CFDictionaryGetTypeID()) {
       NSDictionary* dictionary_ns = base::mac::CFToNSCast(
           base::mac::CFCastStrict<CFDictionaryRef>(property_cf));
       base::mac::ScopedLaunchData dictionary_launch(
           LaunchDataAlloc(LAUNCH_DATA_DICTIONARY));
 
       for (NSString* key in dictionary_ns) {
         if (![key isKindOfClass:[NSString class]]) {
           return nullptr;
         }
 
         CFPropertyListRef value_cf =
-            implicit_cast<CFPropertyListRef>([dictionary_ns objectForKey:key]);
+            crashpad::implicit_cast<CFPropertyListRef>([dictionary_ns objectForKey:key]);
         launch_data_t value_launch = CFPropertyToLaunchData(value_cf);
         if (!value_launch) {
           return nullptr;
         }
 
         LaunchDataDictInsert(dictionary_launch, value_launch, [key UTF8String]);
       }
 
       data_launch = dictionary_launch.release();
 
     } else if (type_id_cf == CFArrayGetTypeID()) {
       NSArray* array_ns = base::mac::CFToNSCast(
           base::mac::CFCastStrict<CFArrayRef>(property_cf));
       base::mac::ScopedLaunchData array_launch(
           LaunchDataAlloc(LAUNCH_DATA_ARRAY));
       size_t index = 0;
 
       for (id element_ns in array_ns) {
         CFPropertyListRef element_cf =
-            implicit_cast<CFPropertyListRef>(element_ns);
+            crashpad::implicit_cast<CFPropertyListRef>(element_ns);
         launch_data_t element_launch = CFPropertyToLaunchData(element_cf);
         if (!element_launch) {
           return nullptr;
         }
 
         LaunchDataArraySetIndex(array_launch, element_launch, index++);
       }
 
       data_launch = array_launch.release();
 
@@ skipping 53 matching lines @@
           CFCopyTypeIDDescription(type_id_cf));
       DLOG(ERROR) << "unable to convert CFTypeID " << type_id_cf << " ("
                   << base::SysCFStringRefToUTF8(type_name_cf) << ")";
     }
 
     return data_launch;
   }
 }
 
 }  // namespace crashpad