Remove FontVariationAxis.InvalidFormatException.

Use IllegalArgumentException instead.

Bug: 37769084
Bug: 37765945
Test: am instrument -w -e class android.widget.cts.TextViewTest
      android.widget.cts/android.support.test.runner.AndroidJUnitRunner
Test: am instrument -w -e class android.graphics.cts.TypefaceTest
      android.graphics.cts/android.support.test.runner.AndroidJUnitRunner
Test: am instrument -w -e class android.graphics.cts.PaintTest
      android.graphics.cts/android.support.test.runner.AndroidJUnitRunner
Test: am instrument -w -e class android.graphics.cts.FontVariationAxisTest
      android.graphics.cts/android.support.test.runner.AndroidJUnitRunner
Test: am instrument -w -e class android.text.VariationParserTest
      com.android.frameworks.coretests/\
      android.support.test.runner.AndroidJUnitRunner

Change-Id: I50b70e3e7e37585c937dcce2416a83353de62a5d