Update third_party/protobuf to protobuf-v3.0.0-beta-3

third_party/protobuf/objectivec/GPBExtensionInternals.m

 // Protocol Buffers - Google's data interchange format
 // Copyright 2008 Google Inc.  All rights reserved.
 // https://developers.google.com/protocol-buffers/
 //
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 // notice, this list of conditions and the following disclaimer.
@@ skipping 15 matching lines @@
 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 #import "GPBExtensionInternals.h"
 
 #import <objc/runtime.h>
 
 #import "GPBCodedInputStream_PackagePrivate.h"
-#import "GPBCodedOutputStream.h"
+#import "GPBCodedOutputStream_PackagePrivate.h"
 #import "GPBDescriptor_PackagePrivate.h"
 #import "GPBMessage_PackagePrivate.h"
 #import "GPBUtilities_PackagePrivate.h"
 
 static id NewSingleValueFromInputStream(GPBExtensionDescriptor *extension,
                                         GPBCodedInputStream *input,
                                         GPBExtensionRegistry *extensionRegistry,
                                         GPBMessage *existingValue)
     __attribute__((ns_returns_retained));
 
@@ skipping 324 matching lines @@
           [input readMessage:message extensionRegistry:extensionRegistry];
         }
       }
 
       return message;
     }
   }
 
   return nil;
 }