Java methods can now be passed JavaRef parameters directly; remove calls
to .obj() that were being used to convert JavaRef to bare jobject, in
preparation for requiring JavaRef to be used.

This CL only fixes cases that can be fixed by removing the precise
string ".obj()" from a function call and does not introduce any other
changes (though it was run through git cl format to rewrap lines
afterward). This is to enable rubberstamp reviews.

There are a much smaller number of nontrivial changes required to
completely eliminate use of bare jobject as Java method parameters,
which will come in followup CLs for proper review.

BUG=506850
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_site_isolation

Review-Url: https://codereview.chromium.org/2237943002
Cr-Commit-Position: refs/heads/master@{#412237}