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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
bool needs_begin_frames) {
  SetupFrameRate(false);
  begin_frame_timer_->SetActive(needs_begin_frames);
  if (software_output_device_) {
    software_output_device_->SetActive(needs_begin_frames && painting_, false);
  }
}
void CopyBitmapTo(
    const SkBitmap& destination,
    const SkBitmap& source,
    const gfx::Rect& pos) {
  char* src = static_cast<char*>(source.getPixels());
  char* dest = static_cast<char*>(destination.getPixels());
  int pixelsize = source.bytesPerPixel();
  int width = pos.x() + pos.width() <= destination.width() ? pos.width()
    : pos.width() - ((pos.x() + pos.width()) - destination.width());
  int height = pos.y() + pos.height() <= destination.height() ? pos.height()
    : pos.height() - ((pos.y() + pos.height()) - destination.height());
  if (width > 0 && height > 0) {
    for (int i = 0; i < height; i++) {
      memcpy(dest + ((pos.y() + i) * destination.width() + pos.x()) * pixelsize,
        src + (i * source.width()) * pixelsize,
        width * pixelsize);
    }
  }
  destination.notifyPixelsChanged();
}
void OffScreenRenderWidgetHostView::OnPaint(