Update to 60.7.0

From Piotr Meyer, thank you.

Changelog:
changed:
    Font and date adjustments to accommodate the new Reiwa era in Japan

fixed:
#CVE-2019-9815: Disable hyperthreading on content JavaScript threads on macOS
#CVE-2019-9816: Type confusion with object groups and UnboxedObjects
#CVE-2019-9817: Stealing of cross-domain images using canvas
#CVE-2019-9818: Use-after-free in crash generation server
#CVE-2019-9819: Compartment mismatch with fetch API
#CVE-2019-9820: Use-after-free of ChromeEventHandler by DocShell
#CVE-2019-11691: Use-after-free in XMLHttpRequest
#CVE-2019-11692: Use-after-free removing listeners in the event listener manager
#CVE-2019-11693: Buffer overflow in WebGL bufferdata on Linux
#CVE-2019-7317: Use-after-free in png_image_free of libpng library
#CVE-2019-9797: Cross-origin theft of images with createImageBitmap
#CVE-2018-18511: Cross-origin theft of images with ImageBitmapRenderingContext
#CVE-2019-11694: Uninitialized memory memory leakage in Windows sandbox
#CVE-2019-11698: Theft of user history data through drag and drop of hyperlinks to and from bookmarks
#CVE-2019-5798: Out-of-bounds read in Skia
#CVE-2019-9800: Memory safety bugs fixed in Firefox 67 and Firefox ESR 60.7

(ryoon)