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* Electron version: 1.7.11
* Operating system: win10 x64

i want record every frame to make a video,

### Expected behavior

stop painting page, until call startPainting()

### Actual behavior

not stop painting page

### How to reproduce
```js
const electron = require('electron');
const fs = require('fs');
const app = electron.app
const BrowserWindow = electron.BrowserWindow

let mainWindow

// app.disableHardwareAcceleration()
function createWindow() {
  mainWindow = new BrowserWindow({
    width: 480, height: 800, frame: false, resizable: false, // show: false,
    webPreferences: {
      offscreen: true
    }
  })
  // mainWindow = new BrowserWindow({ width: 480, height: 800 })
  var i = 0;
  mainWindow.webContents.on('paint', (event, dirty, image) => {
    mainWindow.webContents.stopPainting()
    const data = image.toPNG()
    fs.writeFileSync('./f/' + i++ + '.png', data)
    // mainWindow.webContents.startPainting()
  })
  mainWindow.webContents.setFrameRate(1)

  mainWindow.on('closed', function () {
    mainWindow = null
  })
  
  var url = 'https://github.com';
  mainWindow.loadURL(url)
  //mainWindow.webContents.openDevTools()

}

app.on('ready', createWindow)
app.on('window-all-closed', function () {
  if (process.platform !== 'darwin') {
    app.quit()
  }
})
app.on('activate', function () {
  if (mainWindow === null) {
    createWindow()
  }
})
```

atom/browser/osr/osr_render_widget_host_view.cc
int frame_rate_threshold_us)
    : view_(view),
      frame_retry_count_(0),
      next_frame_time_(base::TimeTicks::Now()),
      frame_duration_(base::TimeDelta::FromMicroseconds(
        frame_rate_threshold_us)),
      weak_ptr_factory_(this) {
    last_time_ = base::Time::Now();
  }
  void GenerateCopyFrame(const gfx::Rect& damage_rect) {
    if (!view_->render_widget_host())
      return;
    std::unique_ptr<cc::CopyOutputRequest> request =
        cc::CopyOutputRequest::CreateBitmapRequest(base::Bind(
            &AtomCopyFrameGenerator::CopyFromCompositingSurfaceHasResult,
            weak_ptr_factory_.GetWeakPtr(),
            damage_rect));
    request->set_area(gfx::Rect(view_->GetPhysicalBackingSize()));
    view_->GetRootLayer()->RequestCopyOfOutput(std::move(request));
  }
  void set_frame_rate_threshold_us(int frame_rate_threshold_us) {
    frame_duration_ = base::TimeDelta::FromMicroseconds(
      frame_rate_threshold_us);
  }
 private:
  void CopyFromCompositingSurfaceHasResult(
      const gfx::Rect& damage_rect,
      std::unique_ptr<cc::CopyOutputResult> result) {
    if (result->IsEmpty() || result->size().IsEmpty() ||
        !view_->render_widget_host()) {