Use client-side rendering in tests not specifically about SSR

It looks like the usage of renderToString() is a copypasta that spread from a test above which was specifically about SSR. I am changing the tests about non-SSR specific warnings to run on the client so we can better track them with Fiber.

scripts/fiber/tests-failing.txt

@@ -22,10 +22,6 @@ src/renderers/dom/shared/__tests__/ReactDOM-test.js
 src/renderers/dom/shared/__tests__/ReactDOMComponent-test.js
 * should clean up input value tracking
 * should clean up input textarea tracking
-* gives source code refs for unknown prop warning
-* gives source code refs for unknown prop warning for update render
-* gives source code refs for unknown prop warning for exact elements 
-* gives source code refs for unknown prop warning for exact elements in composition 
 
 src/renderers/dom/shared/__tests__/ReactDOMTextComponent-test.js
 * can reconcile text merged by Node.normalize() alongside other elements

scripts/fiber/tests-passing-except-dev.txt

@@ -9,7 +9,6 @@ src/renderers/dom/shared/__tests__/ReactDOMComponent-test.js
 * gives useful context in warnings
 * should warn about incorrect casing on properties (ssr)
 * should warn about incorrect casing on event handlers (ssr)
-* should warn about class
 
 src/renderers/dom/shared/__tests__/ReactMount-test.js
 * should warn if mounting into dirty rendered markup

scripts/fiber/tests-passing.txt

@@ -692,7 +692,12 @@ src/renderers/dom/shared/__tests__/ReactDOMComponent-test.js
 * should throw when an attack vector is used
 * should warn about incorrect casing on properties
 * should warn about incorrect casing on event handlers
+* should warn about class
 * should warn about props that are no longer supported
+* gives source code refs for unknown prop warning
+* gives source code refs for unknown prop warning for update render
+* gives source code refs for unknown prop warning for exact elements 
+* gives source code refs for unknown prop warning for exact elements in composition 
 * should suggest property name if available
 
 src/renderers/dom/shared/__tests__/ReactDOMComponentTree-test.js

src/renderers/dom/shared/__tests__/ReactDOMComponent-test.js

@@ -1436,7 +1436,7 @@ describe('ReactDOMComponent', () => {
 
     it('should warn about class', () => {
       spyOn(console, 'error');
-      ReactDOMServer.renderToString(React.createElement('div', {class: 'muffins'}));
+      ReactTestUtils.renderIntoDocument(React.createElement('div', {class: 'muffins'}));
       expectDev(console.error.calls.count()).toBe(1);
       expectDev(console.error.calls.argsFor(0)[0]).toContain('className');
     });
@@ -1455,8 +1455,8 @@ describe('ReactDOMComponent', () => {
 
     it('gives source code refs for unknown prop warning', () => {
       spyOn(console, 'error');
-      ReactDOMServer.renderToString(<div class="paladin"/>);
-      ReactDOMServer.renderToString(<input type="text" onclick="1"/>);
+      ReactTestUtils.renderIntoDocument(<div class="paladin"/>);
+      ReactTestUtils.renderIntoDocument(<input type="text" onclick="1"/>);
       expectDev(console.error.calls.count()).toBe(2);
       expect(
         normalizeCodeLocInfo(console.error.calls.argsFor(0)[0])
@@ -1475,10 +1475,10 @@ describe('ReactDOMComponent', () => {
       spyOn(console, 'error');
       var container = document.createElement('div');
 
-      ReactDOMServer.renderToString(<div className="paladin" />, container);
+      ReactTestUtils.renderIntoDocument(<div className="paladin" />, container);
       expectDev(console.error.calls.count()).toBe(0);
 
-      ReactDOMServer.renderToString(<div class="paladin" />, container);
+      ReactTestUtils.renderIntoDocument(<div class="paladin" />, container);
       expectDev(console.error.calls.count()).toBe(1);
       expect(
         normalizeCodeLocInfo(console.error.calls.argsFor(0)[0])
@@ -1491,7 +1491,7 @@ describe('ReactDOMComponent', () => {
     it('gives source code refs for unknown prop warning for exact elements ', () => {
       spyOn(console, 'error');
 
-      ReactDOMServer.renderToString(
+      ReactTestUtils.renderIntoDocument(
         <div className="foo1">
         <div class="foo2"/>
         <div onClick="foo3"/>
@@ -1550,7 +1550,7 @@ describe('ReactDOMComponent', () => {
         }
       }
 
-      ReactDOMServer.renderToString(<Parent />, container);
+      ReactTestUtils.renderIntoDocument(<Parent />, container);
 
       expectDev(console.error.calls.count()).toBe(2);