Expose authdataresult.credential.secret in public header. (#3089)

Author: Yue-Wang-Google

Firebase/Auth/Source/Auth/FIRAuthDataResult_Internal.h

@@ -22,12 +22,6 @@ NS_ASSUME_NONNULL_BEGIN
 
 @interface FIRAuthDataResult () <NSSecureCoding>
 
-/** @property credential
-    @brief The updated OAuth credential after the sign-in, link and reauthenticate action.
-    @detail This property is for OAuth sign in only.
- */
-@property(nonatomic, readonly, nullable) FIROAuthCredential *credential;
-
 /** @fn initWithUser:additionalUserInfo:
     @brief Designated initializer.
     @param user The signed in user reference.

Firebase/Auth/Source/AuthProvider/OAuth/FIROAuthCredential_Internal.h

@@ -42,13 +42,6 @@ NS_ASSUME_NONNULL_BEGIN
  */
 @property(nonatomic, readonly, nullable) NSString *pendingToken;
 
-/** @property secret
-    @brief The secret associated with this credential. This will be nil for OAuth 2.0 providers.
-    @detail OAuthCredential already exposes a providerId getter. This will help the developer
-        determine whether an access token/secret pair is needed.
- */
-@property(nonatomic, readonly, nullable) NSString *secret;
-
 /** @fn initWithProviderId:IDToken:accessToken:secret:pendingToken
     @brief Designated initializer.
     @param providerID The provider ID associated with the credential being created.

Firebase/Auth/Source/Public/FIRAuthDataResult.h

@@ -17,6 +17,7 @@
 #import <Foundation/Foundation.h>
 
 @class FIRAdditionalUserInfo;
+@class FIRAuthCredential;
 @class FIRUser;
 
 NS_ASSUME_NONNULL_BEGIN
@@ -44,6 +45,13 @@ NS_SWIFT_NAME(AuthDataResult)
  */
 @property(nonatomic, readonly, nullable) FIRAdditionalUserInfo *additionalUserInfo;
 
+/** @property credential
+    @brief This property will be non-nil after a successful headful-lite sign-in via
+        signInWithProvider:UIDelegate:. May be used to obtain the accessToken and/or IDToken
+        pertaining to a recently signed-in user.
+ */
+@property(nonatomic, readonly, nullable) FIRAuthCredential *credential;
+
 @end
 
 NS_ASSUME_NONNULL_END

Firebase/Auth/Source/Public/FIROAuthCredential.h

@@ -36,6 +36,13 @@ NS_SWIFT_NAME(OAuthCredential)
  */
 @property(nonatomic, readonly, nullable) NSString *accessToken;
 
+/** @property secret
+    @brief The secret associated with this credential. This will be nil for OAuth 2.0 providers.
+    @detail OAuthCredential already exposes a providerId getter. This will help the developer
+        determine whether an access token/secret pair is needed.
+ */
+@property(nonatomic, readonly, nullable) NSString *secret;
+
 /** @fn init
     @brief This class is not supposed to be instantiated directly.
  */