[SPARK-18901][FOLLOWUP][ML] Require in LR LogisticAggregator is redundant

## What changes were proposed in this pull request?

This is a follow-up PR of #17478.

## How was this patch tested?

Existing tests

Author: wangmiao1981 <[email protected]>

Closes #17754 from wangmiao1981/followup.

Author: wangmiao1981

mllib/src/main/scala/org/apache/spark/ml/classification/LinearSVC.scala

@@ -458,9 +458,7 @@ private class LinearSVCAggregator(
    */
   def add(instance: Instance): this.type = {
     instance match { case Instance(label, weight, features) =>
-      require(weight >= 0.0, s"instance weight, $weight has to be >= 0.0")
-      require(numFeatures == features.size, s"Dimensions mismatch when adding new instance." +
-        s" Expecting $numFeatures but got ${features.size}.")
+
       if (weight == 0.0) return this
       val localFeaturesStd = bcFeaturesStd.value
       val localCoefficients = coefficientsArray
@@ -512,6 +510,7 @@ private class LinearSVCAggregator(
    * @return This LinearSVCAggregator object.
    */
   def merge(other: LinearSVCAggregator): this.type = {
+
     if (other.weightSum != 0.0) {
       weightSum += other.weightSum
       lossSum += other.lossSum

mllib/src/main/scala/org/apache/spark/ml/regression/LinearRegression.scala

@@ -971,9 +971,6 @@ private class LeastSquaresAggregator(
    */
   def add(instance: Instance): this.type = {
     instance match { case Instance(label, weight, features) =>
-      require(dim == features.size, s"Dimensions mismatch when adding new sample." +
-        s" Expecting $dim but got ${features.size}.")
-      require(weight >= 0.0, s"instance weight, $weight has to be >= 0.0")
 
       if (weight == 0.0) return this
 
@@ -1005,8 +1002,6 @@ private class LeastSquaresAggregator(
    * @return This LeastSquaresAggregator object.
    */
   def merge(other: LeastSquaresAggregator): this.type = {
-    require(dim == other.dim, s"Dimensions mismatch when merging with another " +
-      s"LeastSquaresAggregator. Expecting $dim but got ${other.dim}.")
 
     if (other.weightSum != 0) {
       totalCnt += other.totalCnt