Query editor "Explain" query plan is broken

[MattIrv]

• SQL Operations Studio Version: master 8fce79f

Steps to Reproduce:

1. Open a query editor with a connection
2. Run a query
3. Hit "Explain"

Expected behavior: The query plan shows up
Actual behavior: The query plan is blank and the following error gets printed to the console:

Unhandled Promise rejection: Cannot read property 'getBoundingClientRect' of null ; Zone: <root> ; Task: Promise.then ; Value:
zone-node.js:2251
TypeError: Cannot read property 'getBoundingClientRect' of null
zone-node.js:2251
TypeError: Cannot read property 'getBoundingClientRect' of null
    at Object.i [as drawSvgLines] (/Users/mairvine/code/sqlopsstudio/node_modules/html-query-plan/dist/index.min.js:1:1673)
    at Object.i [as showPlan] (/Users/mairvine/code/sqlopsstudio/node_modules/html-query-plan/dist/index.min.js:1:665)
    at QueryPlanComponent.set [as planXml] (file:///Users/mairvine/code/sqlopsstudio/out/sql/parts/queryPlan/queryPlan.component.js:36:20)
    at QueryPlanComponent.ngOnInit (file:///Users/mairvine/code/sqlopsstudio/out/sql/parts/queryPlan/queryPlan.component.js:29:30)
    at checkAndUpdateDirectiveInline (/Users/mairvine/code/sqlopsstudio/node_modules/@angular/core/bundles/core.umd.js:10822:19)
    at checkAndUpdateNodeInline (/Users/mairvine/code/sqlopsstudio/node_modules/@angular/core/bundles/core.umd.js:12245:17)
    at checkAndUpdateNode (/Users/mairvine/code/sqlopsstudio/node_modules/@angular/core/bundles/core.umd.js:12184:16)
    at debugCheckAndUpdateNode (/Users/mairvine/code/sqlopsstudio/node_modules/@angular/core/bundles/core.umd.js:12887:59)
    at debugCheckDirectivesFn (/Users/mairvine/code/sqlopsstudio/node_modules/@angular/core/bundles/core.umd.js:12828:13)
    at Object.eval [as updateDirectives] (ng:///ModuleClass/QueryOutputComponent.ngfactory.js:145:5)

[MattIrv]

May be related to #1425