src/vs/workbench/contrib/terminal/browser/terminalGroup.ts/SplitPaneContainer/resizePanes
class SplitPaneContainer:	resizePanes(relativeSizes: number[]): void {
		if (this._children.length <= 1) {
			return;
		}

		// assign any extra size to last terminal
		relativeSizes[relativeSizes.length - 1] += 1 - relativeSizes.reduce((totalValue, currentValue) => totalValue + currentValue, 0);
		let totalSize = 0;
		for (let i = 0; i < this._splitView.length; i++) {
			totalSize += this._splitView.getViewSize(i);
		}
		for (let i = 0; i < this._splitView.length; i++) {
			this._splitView.resizeView(i, totalSize * relativeSizes[i]);
		}
	}