Convert denormalised-voiced-japanese-chars.html to a reference test.

LayoutTests/platform/win/fast/encoding/denormalised-voiced-japanese-chars-expected.txt

-layer at (0,0) size 800x600
-  LayoutView at (0,0) size 800x600
-layer at (0,0) size 800x248
-  LayoutBlockFlow {HTML} at (0,0) size 800x247.63
-    LayoutBlockFlow {BODY} at (8,8) size 784x223.63
-      LayoutBlockFlow (anonymous) at (0,0) size 784x54
-        LayoutText {#text} at (0,0) size 766x53
-          text run at (0,0) width 766: "This test checks that the decomposed unicode version of voiced japanese hiragana and katakana characters are rendered"
-          text run at (0,18) width 763: "the same as the precomposed version. This test is a pixel-test, and passes when the text in the two heading elements are"
-          text run at (0,36) width 60: "identical."
-      LayoutBlockFlow {H2} at (0,73.91) size 784x27
-        LayoutText {#text} at (0,0) size 160x26
-          text run at (0,0) width 160: "\x{30CF}\x{3099}\x{30CA}\x{30CA}\x{3068}\x{30CF}\x{309A}\x{30CA}\x{30DE}"
-      LayoutBlockFlow {P} at (0,120.81) size 784x18
-        LayoutText {#text} at (0,0) size 166x17
-          text run at (0,0) width 166: "The above is decomposed"
-      LayoutBlockFlow {H2} at (0,158.72) size 784x27
-        LayoutText {#text} at (0,0) size 160x26
-          text run at (0,0) width 160: "\x{30D0}\x{30CA}\x{30CA}\x{3068}\x{30D1}\x{30CA}\x{30DE}"
-      LayoutBlockFlow {P} at (0,205.63) size 784x18
-        LayoutText {#text} at (0,0) size 172x17
-          text run at (0,0) width 172: "The above is precomposed"