bug(docs): fix scroll broken on safari #247

[amcdnl]

Addresses #247 where scrolling doesn't work on safari.

[jelbourn]

@mmalerba should this be necessary?

[willshowell]

@amcdnl Changing the selector to .mat-drawer-content here should do it:

material.angular.io/src/app/pages/component-sidenav/component-sidenav.scss

Lines 8 to 16 in 047b733

	.docs-component-viewer-sidenav-container {
	width: 100%;
	.mat-sidenav-content {
	position: absolute;
	right: 0;
	left: 0;
	}
	}

[amcdnl]

@jelbourn @willshowell - Ya, that works better. Updated.