Fix wpt/css/css-masking/mask-svg-content/mask-text-001.svg

The test has fixed dimensions of 100x100 pixels - the reference does
not. Add same fixed dimensions to the reference to get the same clipping
behavior.

Bug: 890755
Change-Id: Ib3d12ad1f7ace05027b81b9c683158490ae116ab
Reviewed-on: https://chromium-review.googlesource.com/1256568Reviewed-by: Stephen Chenney <schenney@chromium.org>
Commit-Queue: Fredrik Söderquist <fs@opera.com>
Cr-Commit-Position: refs/heads/master@{#595936}

third_party/WebKit/LayoutTests/TestExpectations

@@ -2826,7 +2826,6 @@ crbug.com/626703 external/wpt/webvtt/rendering/cues-with-video/processing-model/
 crbug.com/626703 external/wpt/webvtt/rendering/cues-with-video/processing-model/align_center_position_lt_50_size_gt_maximum_size.html [ Failure ]
 crbug.com/626703 external/wpt/webvtt/rendering/cues-with-video/processing-model/align_center.html [ Failure ]
 crbug.com/626703 external/wpt/webvtt/rendering/cues-with-video/processing-model/regions/viewportanchor_y_50_percent.html [ Timeout ]
-crbug.com/626703 external/wpt/css/css-masking/mask-svg-content/mask-text-001.svg [ Failure ]
 crbug.com/626703 external/wpt/css/css-backgrounds/border-image-width-008.html [ Failure ]
 crbug.com/626703 external/wpt/content-security-policy/generic/only-valid-whitespaces-are-allowed.html [ Timeout ]
 crbug.com/626703 virtual/outofblink-cors-ns/external/wpt/referrer-policy/css-integration/svg/internal-stylesheet.html [ Timeout ]

third_party/WebKit/LayoutTests/external/wpt/css/css-masking/mask-svg-content/reference/mask-text-001-ref.svg

-<svg xmlns="http://www.w3.org/2000/svg" xmlns:html="http://www.w3.org/1999/xhtml">
+<svg xmlns="http://www.w3.org/2000/svg" xmlns:html="http://www.w3.org/1999/xhtml"
+     width="100px" height="100px">
 <g id="testmeta">
 	<title>CSS Masking: Reftest reference</title>
 	<html:link rel="author" title="Dirk Schulze" href="mailto:dschulze@adobe.com"/>
 	<metadata class="flags">svg</metadata>
 </g>
 <text fill="#000" font-family="Ahem" font-size="12px" transform="rotate(90 50 50)" x="50" y="50">foobar</text>
-</svg>
+</svg>
\ No newline at end of file