add warning or trim for event handler with extra space in template

[carrytao]

Vue.js version

2.0.1

Reproduction Link

http://jsbin.com/faremewici/2/edit?html,js,console,output

Steps to reproduce

As you can see , @click=" onClickHandler " has extra space.
then click the link in output

What is Expected?

the console should warn that event handler doesn't exist or execute onClickHandler directly

What is actually happening?

the console output nothing

Even in webpack dev environment, Vue doesn't show any warning.
I expect Vue can give a warning in this situation or just trim it to execute onClickHandler method.

[posva]

@hechentao I'm curious, how did you find yourself with spaces around that handle?

[carrytao]

@posva Because I find the handler is not called, so I look into the code again and find spaces.
That's not important. Just need a warning for it in dev environment.

[posva]

@hechentao But, how were the spaces introduces in the first place?

[carrytao]

@posva Yes. I just made a mistake. I wrote code like@click="handler ". Adding a warning in this case can make Vue more friendly.