Fix typedarray tests.

1. Fixed typo. lenght -> length. Arbitary -> Arbitrary.
2. TypedArray DataView property getters should throw TypeError when called on
    incompatible types.
3. Should not use integers as keys in the arbitrary-properties test.

R=dslomov@chromium.org, yangguo@chromium.org

Review URL: https://codereview.chromium.org/652603002

Patch from Xueqiao Xu <xuq@google.com>.

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24551 ce2b1a6d-e550-0410-aec6-3dcde31c8c00