Android-Studio：Cannot reload AVD list

今天用Android-Studio时点击"RUN"后出现如下错误，特此记录一下解决方案。

Cannot reload AVD list: cvc-enumeration-valid: Value '280dpi' is not facet-valid with respect to enumeration '[ldpi, mdpi, tvdpi, hdpi, xhdpi, 400dpi, xxhdpi, 560dpi, xxxhdpi]'. It must be a value from the enumeration.
Error parsing D:sdkforasandroid-sdk-windowssystem-imagesandroid-22android-weararmeabi-v7adevices.xml
cvc-enumeration-valid: Value '280dpi' is not facet-valid with respect to enumeration '[ldpi, mdpi, tvdpi, hdpi, xhdpi, 400dpi, xxhdpi, 560dpi, xxxhdpi]'. It must be a value from the enumeration.

###用/sdk/tools/lib/devices.xml 去替换 ###system-imagesandroid-2Xandroid-wearx86devices.xml ###system-imagesandroid-2Xandroid-weararmeabi-v7adevices.xml中的devices.xml