* Output of `node_modules/.bin/electron --version`: 3.0.9 (and up)
* Operating System (Platform and Version): Windows 10
* Output of `node_modules/.bin/electron --version` on last known working Electron version (if applicable): 2.0.x

**Expected Behavior**
Pressing `Ctrl + Shift + V` should result in one paste event only.

**Actual behavior**
Pressing `Ctrl + Shift + V` results in two paste events only.

**To Reproduce**
@brenca was nice enough to make a Fiddle (https://gist.github.com/brenca/e0ca153755979bed51a991e9d8c185bb). 

**Additional Notes**
A few notes that are interesting:
 * This bug is Windows-only.
 * Not registering a `paste` handler: No issue
 * Not calling `event.preventDefault()` or `event.returnValue = false`: No issue
 * Just clicking on a `MenuItem` that calls `webContents.pasteAndMatchStyle()`: No issue
 * Not registering a `MenuItem` with an accelerator: No issue
 * Chromium 66 does not have this issue


atom/browser/ui/accelerator_util.cc
const ui::Accelerator& accelerator) {
  if (base::ContainsKey(*table, accelerator)) {
    const accelerator_util::MenuItem& item = (*table)[accelerator];
    if (item.model->IsEnabledAt(item.position)) {
      const auto event_flags =
          accelerator.MaskOutKeyEventFlags(accelerator.modifiers());
      item.model->ActivatedAt(item.position, event_flags);
      return true;
    }
  }
  return false;
}
}