Devtools: Add screenshot button to device mode toolbar.

third_party/WebKit/Source/devtools/front_end/emulation/DeviceModeWrapper.js

Index: third_party/WebKit/Source/devtools/front_end/emulation/DeviceModeWrapper.js
diff --git a/third_party/WebKit/Source/devtools/front_end/emulation/DeviceModeWrapper.js b/third_party/WebKit/Source/devtools/front_end/emulation/DeviceModeWrapper.js
index 2fca7229288837bfeeef2ccd7dfc9b9b339a1708..f1cfe7f1c79a44a681a1dcfb0718064c65a5a039 100644
--- a/third_party/WebKit/Source/devtools/front_end/emulation/DeviceModeWrapper.js
+++ b/third_party/WebKit/Source/devtools/front_end/emulation/DeviceModeWrapper.js
@@ -30,6 +30,17 @@ WebInspector.DeviceModeWrapper.prototype = {
     },
 
     /**
+     * @return {boolean}
+     */
+    _captureScreenshot: function()
+    {
+        if (!this._deviceModeView)
+            return false;
+        this._deviceModeView.captureScreenshot();
+        return true;
+    },
+
+    /**
      * @param {boolean} force
      */
     _update: function(force)
@@ -80,6 +91,8 @@ WebInspector.DeviceModeWrapper.ActionDelegate.prototype = {
                 WebInspector.DeviceModeView._wrapperInstance._toggleDeviceMode();
                 return true;
             }
+            if (actionId === "emulation.capture-screenshot")
+                return WebInspector.DeviceModeView._wrapperInstance._captureScreenshot();
         }
         return false;
     }