Build out more complete code coverage in the tests.

Author: thomasvl

objectivec/GPBDescriptor.m

@@ -1027,10 +1027,6 @@ - (BOOL)isRepeated {
   return GPBExtensionIsRepeated(description_);
 }
 
-- (BOOL)isMap {
-  return (description_->options & GPBFieldMapKeyMask) != 0;
-}
-
 - (BOOL)isPackable {
   return GPBExtensionIsPacked(description_);
 }

objectivec/GPBUnknownField.m

@@ -97,6 +97,7 @@ - (BOOL)isEqual:(id)object {
   if (self == object) return YES;
   if (![object isKindOfClass:[GPBUnknownField class]]) return NO;
   GPBUnknownField *field = (GPBUnknownField *)object;
+  if (number_ != field->number_) return NO;
   BOOL equalVarint =
       (mutableVarintList_.count == 0 && field->mutableVarintList_.count == 0) ||
       [mutableVarintList_ isEqual:field->mutableVarintList_];
@@ -202,8 +203,9 @@ - (size_t)serializedSizeAsMessageSetExtension {
 }
 
 - (NSString *)description {
-  NSMutableString *description = [NSMutableString
-      stringWithFormat:@"<%@ %p>: Field: %d {\n", [self class], self, number_];
+  NSMutableString *description =
+      [NSMutableString stringWithFormat:@"<%@ %p>: Field: %d {\n",
+       [self class], self, number_];
   [mutableVarintList_
       enumerateValuesWithBlock:^(uint64_t value, NSUInteger idx, BOOL *stop) {
 #pragma unused(idx, stop)