refactor(gax): make RetryingContext overload primary and simplify streaming exception wrap (#13995)

Author: macastelaz

sdk-platform-java/gax-java/gax/src/main/java/com/google/api/gax/rpc/ApiResultRetryAlgorithm.java

@@ -45,6 +45,15 @@ class ApiResultRetryAlgorithm<ResponseT> extends BasicResultRetryAlgorithm<Respo
       @Nullable Throwable previousThrowable,
       @Nullable ResponseT previousResponse,
       TimedAttemptSettings previousSettings) {
+    return createNextAttempt(null, previousThrowable, previousResponse, previousSettings);
+  }
+
+  @Override
+  public @Nullable TimedAttemptSettings createNextAttempt(
+      @Nullable RetryingContext context,
+      @Nullable Throwable previousThrowable,
+      @Nullable ResponseT previousResponse,
+      TimedAttemptSettings previousSettings) {
     if (previousThrowable instanceof UnauthenticatedException
         && ((UnauthenticatedException) previousThrowable).isRetryable()
         && previousSettings.getOverallAttemptCount() == previousSettings.getAttemptCount()) {
@@ -64,15 +73,6 @@ class ApiResultRetryAlgorithm<ResponseT> extends BasicResultRetryAlgorithm<Respo
     return null;
   }
 
-  @Override
-  public @Nullable TimedAttemptSettings createNextAttempt(
-      @Nullable RetryingContext context,
-      @Nullable Throwable previousThrowable,
-      @Nullable ResponseT previousResponse,
-      TimedAttemptSettings previousSettings) {
-    return createNextAttempt(previousThrowable, previousResponse, previousSettings);
-  }
-
   @Override
   public boolean shouldRetry(
       @Nullable Throwable previousThrowable, @Nullable ResponseT previousResponse) {

sdk-platform-java/gax-java/gax/src/main/java/com/google/api/gax/rpc/ServerStreamingAttemptCallable.java

@@ -274,14 +274,7 @@ public void onErrorImpl(Throwable t) {
                   for (Throwable suppressed : unauthenticatedException.getSuppressed()) {
                     newEx.addSuppressed(suppressed);
                   }
-                  if (t instanceof ServerStreamingAttemptException) {
-                    ServerStreamingAttemptException attemptEx = (ServerStreamingAttemptException) t;
-                    t =
-                        new ServerStreamingAttemptException(
-                            newEx, attemptEx.canResume(), attemptEx.hasSeenResponses());
-                  } else {
-                    t = newEx;
-                  }
+                  t = newEx;
                 }
               }
             }