Dereferencing a NULL pointer in SpdyClientSession::clear()
Dereferencing a NULL pointer in SpdyClientSession::clear()

  - At `SpdyClientSession.cc:28`, `static ClassAllocator<SpdyClientSession>
    spdyClientSessionAllocator` creates an instance of `SpdyClientSession`
    using the default constructor.
  - From that point on, `spdyClientSessionAllocator.alloc()`
    essentially calls memcpy on this prototype as an optimization to
    return new instances.
  - The regular usage of `SpdyClientSession` ensures that
    `SpdyClientSession::init()` would be called before its destructor
    is invoked. This init function sets the value of the `mutex`
    pointer inside `SpdyClientSession` from its initial value of
    `NULL`.
  - When `ClassAllocator` is being freed, the destructor on its
    `SpdyClientSession` prototype is called. However, the `mutex`
    inside the prototype is `NULL` and dereferencing it to get to
    `this->mutex->thread_holding` causes a SEGFAULT when the
    destructor is called at process exit.

This closes #323.

rpufky/trafficserver,SolidWallOfCode/trafficserver,pbchou/trafficserver,pbchou/trafficserver,chitianhao/trafficserver,rpufky/trafficserver,chitianhao/trafficserver,pbchou/trafficserver,chenglongwei/trafficserver,PSUdaemon/trafficserver,davidbz/trafficserver,chitianhao/trafficserver,chenglongwei/trafficserver,bryancall/trafficserver,PSUdaemon/trafficserver,clearswift/trafficserver,duke8253/trafficserver,rahmalik/trafficserver,taoyunxing/trafficserver,rahmalik/trafficserver,pbchou/trafficserver,vmamidi/trafficserver,rpufky/trafficserver,SolidWallOfCode/trafficserver,reveller/trafficserver,rpufky/trafficserver,rahmalik/trafficserver,reveller/trafficserver,vmamidi/trafficserver,chenglongwei/trafficserver,rahmalik/trafficserver,clearswift/trafficserver,taoyunxing/trafficserver,chenglongwei/trafficserver,duke8253/trafficserver,duke8253/trafficserver,dyrock/trafficserver,persiaAziz/trafficserver,persiaAziz/trafficserver,chitianhao/trafficserver,bryancall/trafficserver,taoyunxing/trafficserver,duke8253/trafficserver,persiaAziz/trafficserver,davidbz/trafficserver,dyrock/trafficserver,bryancall/trafficserver,dyrock/trafficserver,rpufky/trafficserver,davidbz/trafficserver,chenglongwei/trafficserver,duke8253/trafficserver,taoyunxing/trafficserver,reveller/trafficserver,taoyunxing/trafficserver,rpufky/trafficserver,clearswift/trafficserver,rpufky/trafficserver,rahmalik/trafficserver,davidbz/trafficserver,vmamidi/trafficserver,persiaAziz/trafficserver,rahmalik/trafficserver,taoyunxing/trafficserver,PSUdaemon/trafficserver,davidbz/trafficserver,reveller/trafficserver,clearswift/trafficserver,chenglongwei/trafficserver,bryancall/trafficserver,dyrock/trafficserver,vmamidi/trafficserver,rpufky/trafficserver,clearswift/trafficserver,taoyunxing/trafficserver,davidbz/trafficserver,dyrock/trafficserver,rpufky/trafficserver,PSUdaemon/trafficserver,SolidWallOfCode/trafficserver,SolidWallOfCode/trafficserver,vmamidi/trafficserver,persiaAziz/trafficserver,chitianhao/trafficserver,persiaAziz/trafficserver,chitianhao/trafficserver,clearswift/trafficserver,pbchou/trafficserver,PSUdaemon/trafficserver,persiaAziz/trafficserver,PSUdaemon/trafficserver,vmamidi/trafficserver,SolidWallOfCode/trafficserver,reveller/trafficserver,rahmalik/trafficserver,reveller/trafficserver,rahmalik/trafficserver,reveller/trafficserver,taoyunxing/trafficserver,PSUdaemon/trafficserver,PSUdaemon/trafficserver,clearswift/trafficserver,SolidWallOfCode/trafficserver,SolidWallOfCode/trafficserver,dyrock/trafficserver,bryancall/trafficserver,taoyunxing/trafficserver,clearswift/trafficserver,chitianhao/trafficserver,duke8253/trafficserver,reveller/trafficserver,rahmalik/trafficserver,dyrock/trafficserver,persiaAziz/trafficserver,reveller/trafficserver,clearswift/trafficserver,pbchou/trafficserver,chenglongwei/trafficserver,PSUdaemon/trafficserver,bryancall/trafficserver,duke8253/trafficserver,chenglongwei/trafficserver