Fix table widget grading that was broken in 216dbf3

Switching to using this.state.widgetInfo in the renderer exposed a bug where the table's propTransform was mutating the editor props, resulting in the "correct" answer being blank and therefore unanswerable.

Test Plan:
Answer [[ http://localhost:9000/test.html#content=%7B%22question%22%3A%7B%22content%22%3A%22You%20are%20given%20the%20following%20starting%20numbers%20and%20rules%20for%20two%20sequences%20of%20numbers%3A%5Cn%5CnSequence%20%24x%24%3A%20Starting%20number%3A%20%241%24%2C%20Rule%3A%20add%20%242%24%5Cn%5CnSequence%20%24y%24%3A%20Starting%20number%3A%20%244%24%2C%20Rule%3A%20add%20%248%24%5Cn%5Cn**Fill%20in%20the%20table%20with%20the%20first%20%243%24%20terms%20of%20%24x%24%20and%20%24y%24.%20Then%20plot%20the%20ordered%20pairs%20%24(x%2Cy)%24%20on%20the%20graph%20below%20by%20dragging%20the%20orange%20dots%20to%20the%20correct%20locations.**%20%20%5Cn%20%20%5Cn%5Cn%5B%5B%E2%98%83%20table%201%5D%5D%5Cn%5Cn%5B%5B%E2%98%83%20interactive-graph%201%5D%5D%5Cn%22%2C%22images%22%3A%7B%7D%2C%22widgets%22%3A%7B%22table%201%22%3A%7B%22type%22%3A%22table%22%2C%22graded%22%3Atrue%2C%22options%22%3A%7B%22rows%22%3A3%2C%22columns%22%3A2%2C%22answers%22%3A%5B%5B%221%22%2C%224%22%5D%2C%5B%223%22%2C%2212%22%5D%2C%5B%225%22%2C%2220%22%5D%5D%2C%22headers%22%3A%5B%22%24x%24%22%2C%22%24y%24%22%5D%7D%2C%22version%22%3A%7B%22major%22%3A0%2C%22minor%22%3A0%7D%7D%2C%22interactive-graph%201%22%3A%7B%22type%22%3A%22interactive-graph%22%2C%22graded%22%3Atrue%2C%22options%22%3A%7B%22step%22%3A%5B2%2C2%5D%2C%22backgroundImage%22%3A%7B%22url%22%3Anull%2C%22scale%22%3A1%2C%22bottom%22%3A0%2C%22left%22%3A0%7D%2C%22markings%22%3A%22graph%22%2C%22labels%22%3A%5B%22x%22%2C%22y%22%5D%2C%22showProtractor%22%3Afalse%2C%22showRuler%22%3Afalse%2C%22rulerLabel%22%3A%22%22%2C%22rulerTicks%22%3A10%2C%22range%22%3A%5B%5B-2%2C21%5D%2C%5B-2%2C21%5D%5D%2C%22gridStep%22%3A%5B1%2C1%5D%2C%22snapStep%22%3A%5B0.5%2C0.5%5D%2C%22graph%22%3A%7B%22type%22%3A%22point%22%2C%22numPoints%22%3A3%7D%2C%22correct%22%3A%7B%22type%22%3A%22point%22%2C%22numPoints%22%3A3%2C%22coords%22%3A%5B%5B1%2C4%5D%2C%5B3%2C12%5D%2C%5B5%2C20%5D%5D%7D%7D%2C%22version%22%3A%7B%22major%22%3A0%2C%22minor%22%3A0%7D%7D%7D%7D%2C%22answerArea%22%3A%7B%22type%22%3A%22multiple%22%2C%22options%22%3A%7B%22content%22%3A%22The%20terms%20in%20sequence%20%24y%24%20are%20%5B%5B%E2%98%83%20input-number%201%5D%5D%20times%20the%20terms%20in%20sequence%20%24x%24.%5Cn%5Cn%22%2C%22images%22%3A%7B%7D%2C%22widgets%22%3A%7B%22input-number%201%22%3A%7B%22type%22%3A%22input-number%22%2C%22graded%22%3Atrue%2C%22options%22%3A%7B%22value%22%3A%224%22%2C%22simplify%22%3A%22required%22%2C%22size%22%3A%22normal%22%2C%22inexact%22%3Afalse%2C%22maxError%22%3A0.1%2C%22answerType%22%3A%22number%22%7D%2C%22version%22%3A%7B%22major%22%3A0%2C%22minor%22%3A0%7D%7D%7D%7D%2C%22calculator%22%3Afalse%7D%2C%22itemDataVersion%22%3A%7B%22major%22%3A0%2C%22minor%22%3A1%7D%2C%22hints%22%3A%5B%7B%22content%22%3A%22Sequence%20%24x%24%3A%20Add%20%24%5C%5Cgreen2%24%5Cn%5Cn%24%5C%5Cqquad%5C%5Cbegin%7Balign%7D%5C%5Ctext%7BStarting%20term%7D%26%3A%20%5C%5Cblue1%5C%5C%5C%5C%5Cn%5C%5Ctext%7BTerm%202%7D%26%3A%5C%5Cblue1%2B%5C%5Cgreen2%3D%5C%5Cpink3%5C%5C%5C%5C%5Cn%5C%5Ctext%7BTerm%203%7D%26%3A%5C%5Cpink3%2B%5C%5Cgreen2%3D%5C%5Cpurple5%5C%5Cend%7Balign%7D%24%5Cn%5CnSequence%20%24y%24%3A%20Add%20%24%5C%5Cgray8%24%5Cn%5Cn%24%5C%5Cqquad%5C%5Cbegin%7Balign%7D%5C%5Ctext%7BStarting%20term%7D%26%3A%20%5C%5Cblue4%5C%5C%5C%5C%5Cn%5C%5Ctext%7BTerm%202%7D%26%3A%5C%5Cblue4%2B%5C%5Cgray8%3D%5C%5Cpink%7B12%7D%5C%5C%5C%5C%5Cn%5C%5Ctext%7BTerm%203%7D%26%3A%5C%5Cpink%7B12%7D%2B%5C%5Cgray8%3D%5C%5Cpurple%7B20%7D%5C%5Cend%7Balign%7D%24%5Cn%5Cn%5Cn%5Cn%22%2C%22images%22%3A%7B%7D%2C%22widgets%22%3A%7B%7D%7D%2C%7B%22content%22%3A%22The%20%20ordered%20pairs%20we%20want%20to%20plot%20are%20%24(%5C%5Cblue1%2C%5C%5Cblue4)%2C%20(%5C%5Cpink3%2C%5C%5Cpink%7B12%7D)%2C%20(%5C%5Cpurple5%2C%5C%5Cpurple%7B20%7D)%24.%20%5Cn%5Cn%24%5C%5Cbegin%7Balign%7D%5C%5Cblue1%5C%5Ctimes%5C%5Cgreen4%26%3D%5C%5Cblue4%5C%5C%5C%5C%5Cn%5C%5Cpink3%5C%5Ctimes%5C%5Cgreen4%26%3D%5C%5Cpink%7B12%7D%5C%5C%5C%5C%5Cn%5C%5Cpurple5%5C%5Ctimes%5C%5Cgreen4%26%3D%5C%5Cpurple%7B20%7D%5C%5Cend%7Balign%7D%24%5Cn%5CnSo%20the%20terms%20in%20sequence%20%24y%24%20are%20%24%5C%5Cgreen4%24%20times%20the%20terms%20in%20sequence%20%24x%24.%5Cn%22%2C%22images%22%3A%7B%7D%2C%22widgets%22%3A%7B%7D%7D%2C%7B%22content%22%3A%22Our%20table%20of%20values%20should%20look%20like%20this%3A%5Cn%5Cn%24x%24%20%7C%20%24y%24%20%5Cn-%20%7C%20-%20%7C%20-%5Cn%241%24%20%7C%20%244%24%20%5Cn%243%24%20%7C%20%2412%24%20%5Cn%245%24%20%7C%20%2420%24%5Cn%24%24%5Cn%5CnOur%20graph%20should%20look%20like%20this%3A%5Cn%5Cn!%5B%5D(https%3A%2F%2Fka-perseus-graphie.s3.amazonaws.com%2F577a4d31d20b2356e02accd0cef97710da966c90.png)%5Cn%5CnThe%20terms%20in%20sequence%20%24y%24%20are%20%244%24%20times%20the%20terms%20in%20sequence%20%24x%24.%22%2C%22images%22%3A%7B%22https%3A%2F%2Fka-perseus-graphie.s3.amazonaws.com%2F577a4d31d20b2356e02accd0cef97710da966c90.png%22%3A%7B%22width%22%3A416%2C%22height%22%3A416%7D%7D%2C%22widgets%22%3A%7B%7D%7D%5D%7D | this item ]], score it and see it's graded correctly.

Auditors: aria, michelle