Add unit test for Class.getPrimitiveClass(String).

This method is used to initialize
{Boolean,Byte,Character,Double,Float,Long,Integer,Short,Void}.TYPE

While the method isn't public, testing it in ClassTest keeps the
test logic in one place rather than splitting it over nine tests.

Test: ClassTest
Bug: 73346078
Change-Id: I2adb24190dd6f3d81ec068a2b0a4c793baae579e
1 file changed