[ObjC] Loosen the link between generate messages and roots.

The root class only needs to be started up if the message scopes extensions.
This updates the startup flows so the root is only started when the message
scopes extensions and thus the runtime requires that startup.

Bump the generated source version to account for the new initializer that
doesn't take the rootClass argument.

Fix typo while at it.

PiperOrigin-RevId: 504899046

objectivec/GPBBootstrap.h

@@ -134,7 +134,7 @@
 // Current library runtime version.
 // - Gets bumped when the runtime makes changes to the interfaces between the
 //   generated code and runtime (things added/removed, etc).
-#define GOOGLE_PROTOBUF_OBJC_VERSION 30005
+#define GOOGLE_PROTOBUF_OBJC_VERSION 30006
 
 // Minimum runtime version supported for compiling/running against.
 // - Gets changed when support for the older generated code is dropped.

objectivec/GPBDescriptor.m

@@ -49,7 +49,7 @@ @interface GPBFieldDescriptor ()
 // description has to be long lived, it is held as a raw pointer.
 - (instancetype)initWithFieldDescription:(void *)description
                                     file:(GPBFileDescriptor *)file
-                          decriptorFlags:(GPBDescriptorInitializationFlags)decriptorFlags;
+                         descriptorFlags:(GPBDescriptorInitializationFlags)descriptorFlags;
 
 @end
 
@@ -135,15 +135,11 @@ @implementation GPBDescriptor {
 @synthesize wireFormat = wireFormat_;
 
 + (instancetype)allocDescriptorForClass:(Class)messageClass
-                              rootClass:(Class)rootClass
                                    file:(GPBFileDescriptor *)file
                                  fields:(void *)fieldDescriptions
                              fieldCount:(uint32_t)fieldCount
                             storageSize:(uint32_t)storageSize
                                   flags:(GPBDescriptorInitializationFlags)flags {
-  // The rootClass is no longer used, but it is passed in to ensure it
-  // was started up during initialization also.
-  (void)rootClass;
   NSMutableArray *fields =
       (fieldCount ? [[NSMutableArray alloc] initWithCapacity:fieldCount] : nil);
   BOOL fieldsIncludeDefault = (flags & GPBDescriptorInitializationFlag_FieldsWithDefault) != 0;
@@ -157,7 +153,7 @@ + (instancetype)allocDescriptorForClass:(Class)messageClass
       desc = &(((GPBMessageFieldDescription *)fieldDescriptions)[i]);
     }
     GPBFieldDescriptor *fieldDescriptor =
-        [[GPBFieldDescriptor alloc] initWithFieldDescription:desc file:file decriptorFlags:flags];
+        [[GPBFieldDescriptor alloc] initWithFieldDescription:desc file:file descriptorFlags:flags];
     [fields addObject:fieldDescriptor];
     [fieldDescriptor release];
   }
@@ -172,6 +168,24 @@ + (instancetype)allocDescriptorForClass:(Class)messageClass
   return descriptor;
 }
 
++ (instancetype)allocDescriptorForClass:(Class)messageClass
+                              rootClass:(__unused Class)rootClass
+                                   file:(GPBFileDescriptor *)file
+                                 fields:(void *)fieldDescriptions
+                             fieldCount:(uint32_t)fieldCount
+                            storageSize:(uint32_t)storageSize
+                                  flags:(GPBDescriptorInitializationFlags)flags {
+  // The rootClass is no longer used, but it is passed as [ROOT class] to
+  // ensure it was started up during initialization also when the message
+  // scopes extensions.
+  return [self allocDescriptorForClass:messageClass
+                                  file:file
+                                fields:fieldDescriptions
+                            fieldCount:fieldCount
+                           storageSize:storageSize
+                                 flags:flags];
+}
+
 - (instancetype)initWithClass:(Class)messageClass
                          file:(GPBFileDescriptor *)file
                        fields:(NSArray *)fields
@@ -466,10 +480,10 @@ @implementation GPBFieldDescriptor {
 
 - (instancetype)initWithFieldDescription:(void *)description
                                     file:(GPBFileDescriptor *)file
-                          decriptorFlags:(GPBDescriptorInitializationFlags)decriptorFlags {
+                         descriptorFlags:(GPBDescriptorInitializationFlags)descriptorFlags {
   if ((self = [super init])) {
     BOOL includesDefault =
-        (decriptorFlags & GPBDescriptorInitializationFlag_FieldsWithDefault) != 0;
+        (descriptorFlags & GPBDescriptorInitializationFlag_FieldsWithDefault) != 0;
     GPBMessageFieldDescription *coreDesc;
     if (includesDefault) {
       coreDesc = &(((GPBMessageFieldDescriptionWithDefault *)description)->core);
@@ -486,7 +500,7 @@ - (instancetype)initWithFieldDescription:(void *)description
 
     // If proto3 optionals weren't known (i.e. generated code from an
     // older version), compute the flag for the rest of the runtime.
-    if ((decriptorFlags & GPBDescriptorInitializationFlag_Proto3OptionalKnown) == 0) {
+    if ((descriptorFlags & GPBDescriptorInitializationFlag_Proto3OptionalKnown) == 0) {
       // If it was...
       //  - proto3 syntax
       //  - not repeated/map
@@ -504,7 +518,7 @@ - (instancetype)initWithFieldDescription:(void *)description
 
     // If the ClosedEnum flag wasn't known (i.e. generated code from an older
     // version), compute the flag for the rest of the runtime.
-    if ((decriptorFlags & GPBDescriptorInitializationFlag_ClosedEnumSupportKnown) == 0) {
+    if ((descriptorFlags & GPBDescriptorInitializationFlag_ClosedEnumSupportKnown) == 0) {
       // NOTE: This isn't correct, it is using the syntax of the file that
       // declared the field, not the syntax of the file that declared the
       // enum; but for older generated code, that's all we have and that happens
@@ -540,7 +554,7 @@ - (instancetype)initWithFieldDescription:(void *)description
       // Note: Only fetch the class here, can't send messages to it because
       // that could cause cycles back to this class within +initialize if
       // two messages have each other in fields (i.e. - they build a graph).
-      if ((decriptorFlags & GPBDescriptorInitializationFlag_UsesClassRefs) != 0) {
+      if ((descriptorFlags & GPBDescriptorInitializationFlag_UsesClassRefs) != 0) {
         msgClass_ = coreDesc->dataTypeSpecific.clazz;
       } else {
         // Backwards compatibility for sources generated with older protoc.

objectivec/GPBDescriptor_PackagePrivate.h

@@ -201,6 +201,14 @@ typedef NS_OPTIONS(uint32_t, GPBDescriptorInitializationFlags) {
 }
 
 // fieldDescriptions have to be long lived, they are held as raw pointers.
++ (instancetype)allocDescriptorForClass:(Class)messageClass
+                                   file:(GPBFileDescriptor *)file
+                                 fields:(void *)fieldDescriptions
+                             fieldCount:(uint32_t)fieldCount
+                            storageSize:(uint32_t)storageSize
+                                  flags:(GPBDescriptorInitializationFlags)flags;
+
+// Old interface that took the rootClass.
 + (instancetype)allocDescriptorForClass:(Class)messageClass
                               rootClass:(Class)rootClass
                                    file:(GPBFileDescriptor *)file