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

third_party/protobuf/objectivec/GPBExtensionRegistry.h

 // 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 17 matching lines @@
 // (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 <Foundation/Foundation.h>
 
 @class GPBDescriptor;
 @class GPBExtensionDescriptor;
 
 NS_ASSUME_NONNULL_BEGIN
 
-// A table of known extensions, searchable by name or field number.  When
-// parsing a protocol message that might have extensions, you must provide an
-// ExtensionRegistry in which you have registered any extensions that you want
-// to be able to parse.  Otherwise, those extensions will just be treated like
-// unknown fields.
-//
-// The *Root classes provide +extensionRegistry for the extensions defined in a
-// given file *and* all files it imports.  You can also create a
-// GPBExtensionRegistry, and merge those registries to handle parsing extensions
-// defined from non overlapping files.
-//
-//    GPBExtensionRegistry *registry =
-//        [[[MyProtoFileRoot extensionRegistry] copy] autorelease];
-//    [registry addExtension:[OtherMessage neededExtension];  // Not in MyProtoFile
-//    NSError *parseError = nil;
-//    MyMessage *msg = [MyMessage parseData:data
-//                        extensionRegistry:registry
-//                                    error:&parseError];
-//
+/// A table of known extensions, searchable by name or field number.  When
+/// parsing a protocol message that might have extensions, you must provide a
+/// @c GPBExtensionRegistry in which you have registered any extensions that you
+/// want to be able to parse. Otherwise, those extensions will just be treated
+/// like unknown fields.
+///
+/// The @c *Root classes provide @c +extensionRegistry for the extensions defined
+/// in a given file *and* all files it imports. You can also create a
+/// @c GPBExtensionRegistry, and merge those registries to handle parsing
+/// extensions defined from non overlapping files.
+///
+/// @code
+/// GPBExtensionRegistry *registry =
+///     [[[MyProtoFileRoot extensionRegistry] copy] autorelease];
+/// [registry addExtension:[OtherMessage neededExtension];  // Not in MyProtoFile
+/// NSError *parseError = nil;
+/// MyMessage *msg = [MyMessage parseData:data
+///                     extensionRegistry:registry
+///                                 error:&parseError];
+/// @endcode
 @interface GPBExtensionRegistry : NSObject<NSCopying>
 
+/// Add the given @c GPBExtensionDescriptor to this registry.
+///
+/// @param extension The extension description to add.
 - (void)addExtension:(GPBExtensionDescriptor *)extension;
+
+/// Adds all the extensions from another registry to this registry.
+///
+/// @param registry The registry to merge into this registry.
 - (void)addExtensions:(GPBExtensionRegistry *)registry;
 
+/// Looks for the extension registered for the given field number on a given
+/// @c GPBDescriptor.
+///
+/// @param descriptor  The descriptor to look for a registered extension on.
+/// @param fieldNumber The field number of an extension to look for.
+///
+/// @return The registered @c GPBExtensionDescripto or nil if none was found.
 - (nullable GPBExtensionDescriptor *)extensionForDescriptor:(GPBDescriptor *)descriptor
                                                 fieldNumber:(NSInteger)fieldNumber;
 
 @end
 
 NS_ASSUME_NONNULL_END