fix($http): add check for functions in params

[carlfranz]

Avoid that functions in params object (like getter or setter) will be encoded in the url.

What kind of change does this PR introduce? (Bug fix, feature, docs update, ...)
Bug fix.

What is the current behavior? (You can also link to an open issue here)
Functions in class-object are encoded in url.

What is the new behavior (if this is a feature change)?
Functions in class-object are no more encoded in url

Does this PR introduce a breaking change?
no

Please check if the PR fulfills these requirements

• The commit message follows our guidelines: https://github.com/angular/angular.js/blob/master/CONTRIBUTING.md#commit-message-format
• Tests for the changes have been added (for bug fixes / features)
• Docs have been added / updated (for bug fixes / features)

Other information:
See example of bug here: https://embed.plnkr.co/tspyPWVcm6jMpVDBl6WK/ (open console)

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[gkalpak]

This looks reasonable. (TBD if it is a breaking change or not.)
Could you add some tests?

[gkalpak]

You can incorporate with the previous line:

if (value === null || isUndefined(value) || isFunction(value)) return;

[carlfranz]

done! Can't find how to rename wrong commit :(

[gkalpak]

@carlfranz, you can amend your last commit with git commit --amend.
(Or if you want to change/reorganize multiple commits, git rebase --interactive <COMMIT_RANGE> is powerful tool. Too powerful - ue at your own risk 😛)

[carlfranz]

I created new one with the right commit format at #16133 please delete this. 👍