Correct some accidental renames

[bjchambers]

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---

IDE over-eagerly replaced some occurrences of createAggregator with
createAggregatorForDoFn. This corrects that.

[bjchambers]

R: @tgroh @dhalperi

[tgroh]

LGTM.

[dhalperi]

this one needs revert I believe.

[dhalperi]

Also now needs a merge on top of Kenn's magic.

[bjchambers]

Rebased.

[dhalperi]

Build failing:

[ERROR] COMPILATION ERROR : 
[INFO] -------------------------------------------------------------
[ERROR] /home/jenkins/jenkins-slave/workspace/beam_PreCommit_MavenVerify/sdks/java/core/src/main/java/org/apache/beam/sdk/util/CounterAggregator.java:[43,18] org.apache.beam.sdk.util.CounterAggregator.CounterAggregatorFactory is not abstract and does not override abstract method <InputT,AccumT,OutputT>createAggregator(java.lang.Class<?>,org.apache.beam.sdk.util.ExecutionContext.StepContext,java.lang.String,org.apache.beam.sdk.transforms.Combine.CombineFn<InputT,AccumT,OutputT>) in org.apache.beam.sdk.transforms.Aggregator.AggregatorFactory
[ERROR] /home/jenkins/jenkins-slave/workspace/beam_PreCommit_MavenVerify/sdks/java/core/src/main/java/org/apache/beam/sdk/util/CounterAggregator.java:[50,5] method does not override or implement a method from a supertype
[INFO] 2 errors 

[dhalperi]

Build still failing:

[ERROR] COMPILATION ERROR : 
[INFO] -------------------------------------------------------------
[ERROR] /home/jenkins/jenkins-slave/workspace/beam_PreCommit_MavenVerify/runners/core-java/src/main/java/org/apache/beam/sdk/util/DoFnRunnerBase.java:[348,31] cannot find symbol
  symbol:   method createAggregatorForDoFn(java.lang.Class<capture#1 of ? extends org.apache.beam.sdk.transforms.OldDoFn>,org.apache.beam.sdk.util.ExecutionContext.StepContext,java.lang.String,org.apache.beam.sdk.transforms.Combine.CombineFn<AggInputT,capture#2 of ?,AggOutputT>)
  location: variable aggregatorFactory of type org.apache.beam.sdk.transforms.Aggregator.AggregatorFactory
[INFO] 1 error

[dhalperi]

Still pending, looks like?