Dhiren Serai

Results 2 issues of Dhiren Serai

changed the error message as mentioned in https://github.com/tensorflow/tfjs/issues/1165 also tested in locally with yarn build, format, lint and test. --- This change is [](https://reviewable.io/reviews/tensorflow/tfjs/2848)

cla: no

catching some exceptions which were previously not caught in views of the api and change variable names for readability. # Pull Request Template ## Description Please include a summary of...