This adds information about an exception's caught/uncaught status to the
Runtime.paused event in the data parameter:

{
    "method": "Debugger.paused",
    "params": {
        "callFrames": [
	    [...]
        ],
        "data": {
            "description": "666",
            "type": "number",
            "uncaught": true,  <---
            "value": 666
        },
        "hitBreakpoints": [],
        "reason": "exception"
    }
}

BUG=v8:5530

Review-Url: https://codereview.chromium.org/2488733003
Cr-Commit-Position: refs/heads/master@{#40875}