Reverts third_party/protobuf: Update to HEAD (f52e188fe4)

third_party/protobuf/objectivec/GPBUnknownFieldSet.m

Index: third_party/protobuf/objectivec/GPBUnknownFieldSet.m
diff --git a/third_party/protobuf/objectivec/GPBUnknownFieldSet.m b/third_party/protobuf/objectivec/GPBUnknownFieldSet.m
index a7335f050bcc4f4b681a2478abd7f9aa4ecc5afd..4ddc0d2a4892fc43e53bbecba669d488b301c8de 100644
--- a/third_party/protobuf/objectivec/GPBUnknownFieldSet.m
+++ b/third_party/protobuf/objectivec/GPBUnknownFieldSet.m
@@ -36,6 +36,39 @@
 #import "GPBUtilities.h"
 #import "GPBWireFormat.h"
 
+#pragma mark CFDictionaryKeyCallBacks
+
+// We use a custom dictionary here because our keys are numbers and
+// conversion back and forth from NSNumber was costing us performance.
+// If/when we move to C++ this could be done using a std::map and some
+// careful retain/release calls.
+
+static const void *GPBUnknownFieldSetKeyRetain(CFAllocatorRef allocator,
+                                               const void *value) {
+#pragma unused(allocator)
+  return value;
+}
+
+static void GPBUnknownFieldSetKeyRelease(CFAllocatorRef allocator,
+                                         const void *value) {
+#pragma unused(allocator)
+#pragma unused(value)
+}
+
+static CFStringRef GPBUnknownFieldSetCopyKeyDescription(const void *value) {
+  return CFStringCreateWithFormat(kCFAllocatorDefault, NULL, CFSTR("%d"),
+                                  (int)value);
+}
+
+static Boolean GPBUnknownFieldSetKeyEqual(const void *value1,
+                                          const void *value2) {
+  return value1 == value2;
+}
+
+static CFHashCode GPBUnknownFieldSetKeyHash(const void *value) {
+  return (CFHashCode)value;
+}
+
 #pragma mark Helpers
 
 static void checkNumber(int32_t number) {
@@ -60,12 +93,6 @@ static void CopyWorker(const void *key, const void *value, void *context) {
   [copied release];
 }
 
-// Direct access is use for speed, to avoid even internally declaring things
-// read/write, etc. The warning is enabled in the project to ensure code calling
-// protos can turn on -Wdirect-ivar-access without issues.
-#pragma clang diagnostic push
-#pragma clang diagnostic ignored "-Wdirect-ivar-access"
-
 - (id)copyWithZone:(NSZone *)zone {
   GPBUnknownFieldSet *result = [[GPBUnknownFieldSet allocWithZone:zone] init];
   if (fields_) {
@@ -121,7 +148,7 @@ static void CopyWorker(const void *key, const void *value, void *context) {
 }
 
 - (NSArray *)sortedFields {
-  if (!fields_) return [NSArray array];
+  if (!fields_) return nil;
   size_t count = CFDictionaryGetCount(fields_);
   ssize_t keys[count];
   GPBUnknownField *values[count];
@@ -258,9 +285,13 @@ static void GPBUnknownFieldSetSerializedSizeAsMessageSet(const void *key,
   int32_t number = [field number];
   checkNumber(number);
   if (!fields_) {
-    // Use a custom dictionary here because the keys are numbers and conversion
-    // back and forth from NSNumber isn't worth the cost.
-    fields_ = CFDictionaryCreateMutable(kCFAllocatorDefault, 0, NULL,
+    CFDictionaryKeyCallBacks keyCallBacks = {
+        // See description above for reason for using custom dictionary.
+        0, GPBUnknownFieldSetKeyRetain, GPBUnknownFieldSetKeyRelease,
+        GPBUnknownFieldSetCopyKeyDescription, GPBUnknownFieldSetKeyEqual,
+        GPBUnknownFieldSetKeyHash,
+    };
+    fields_ = CFDictionaryCreateMutable(kCFAllocatorDefault, 0, &keyCallBacks,
                                         &kCFTypeDictionaryValueCallBacks);
   }
   ssize_t key = number;
@@ -322,7 +353,6 @@ static void GPBUnknownFieldSetMergeUnknownFields(const void *key,
 }
 
 - (BOOL)mergeFieldFrom:(int32_t)tag input:(GPBCodedInputStream *)input {
-  NSAssert(GPBWireFormatIsValidTag(tag), @"Got passed an invalid tag");
   int32_t number = GPBWireFormatGetTagFieldNumber(tag);
   GPBCodedInputStreamState *state = &input->state_;
   switch (GPBWireFormatGetTagWireType(tag)) {
@@ -390,6 +420,4 @@ static void GPBUnknownFieldSetMergeUnknownFields(const void *key,
   }
 }
 
-#pragma clang diagnostic pop
-
 @end