Mojo JS Bindings: Mojo handles need a toString() method

Mojo JS Bindings: Mojo handles need a toString() method

The toString() method returns something like this:
"[mojo::Handle 28 0x7f1b48059310]".  If the handle is invalid, typically because it's been closed, then the small integer raw handle value is "null".  The big hex address is included to make it possible to correlate handle strings from before and after a handle has been closed.

BUG=426557

[hansmuller, 2014-10-23 23:15:59]

hansmuller@chromium.org changed reviewers:
+ abarth@chromium.org

[hansmuller, 2014-10-23 23:18:46]

Please take a look.

[abarth-chromium, 2014-10-24 17:13:27]

Test?

https://codereview.chromium.org/646783005/diff/1/mojo/bindings/js/handle.cc
File mojo/bindings/js/handle.cc (right):

https://codereview.chromium.org/646783005/diff/1/mojo/bindings/js/handle.cc#n...
mojo/bindings/js/handle.cc:30: oss << " " << std::hex << this;
I don't think you want to leak the address of |this|.  That can be a security
risk because it leaks where things are arranged in memory...

[hansmuller, 2014-10-24 18:14:02]

I've added a unit test and removed this address from the toString() value.

https://codereview.chromium.org/646783005/diff/1/mojo/bindings/js/handle.cc
File mojo/bindings/js/handle.cc (right):

https://codereview.chromium.org/646783005/diff/1/mojo/bindings/js/handle.cc#n...
mojo/bindings/js/handle.cc:30: oss << " " << std::hex << this;
On 2014/10/24 17:13:27, abarth wrote:
> I don't think you want to leak the address of |this|.  That can be a security
> risk because it leaks where things are arranged in memory...

OK, I've removed that.

[abarth-chromium, 2014-10-24 21:17:10]

LGTM

https://codereview.chromium.org/646783005/diff/20001/mojo/public/js/bindings/...
File mojo/public/js/bindings/core_unittests.js (right):

https://codereview.chromium.org/646783005/diff/20001/mojo/public/js/bindings/...
mojo/public/js/bindings/core_unittests.js:123: var openHandleRE =
/^\[mojo\:\:Handle \d*\]$/ // e.g. "[mojo::Handle 123]"
\d*   ->   \d+