Change SVG layout tree output to be more meaningful and consistent

third_party/WebKit/LayoutTests/platform/mac/svg/custom/text-linking-expected.txt

 layer at (0,0) size 800x600
   LayoutView at (0,0) size 800x600
 layer at (0,0) size 800x600
-  LayoutSVGRoot {svg} at (97,36) size 137x218
-    LayoutSVGHiddenContainer {defs} at (0,0) size 0x0
-      LayoutSVGText {text} at (0,-14) size 167x18 contains 1 chunk(s)
-        LayoutSVGInlineText {#text} at (0,0) size 167x18
+  LayoutSVGRoot {svg} at (0,0) size 800x600
+    LayoutSVGHiddenContainer {defs} at (0,-14) size 200x164
+      LayoutSVGText {text} at (0,-14) size 166.09x18 contains 1 chunk(s)
+        LayoutSVGInlineText {#text} at (0,-14) size 166.09x18
           chunk 1 text run 1 at (0.00,0.00) startOffset 0 endOffset 25 width 166.09: "Referenced character data"
       LayoutSVGPath {path} at (100,140) size 100x10 [fill={[type=SOLID] [color=#000000]}] [data="M 100 150 L 150 140 L 200 150"]
-    LayoutSVGText {text} at (100,36) size 80x18 contains 1 chunk(s)
+    LayoutSVGText {text} at (100,36) size 79.11x18 contains 1 chunk(s)
       LayoutSVGInline {a} at (0,0) size 80x18
         LayoutSVGTSpan {tspan} at (0,0) size 80x18
-          LayoutSVGInlineText {#text} at (0,0) size 80x18
+          LayoutSVGInlineText {#text} at (100,36) size 79.11x18
             chunk 1 text run 1 at (100.00,50.00) startOffset 0 endOffset 13 width 79.11: "tspan in link"
-    LayoutSVGText {text}
+    LayoutSVGText {text} at (0,0) size 0x0
       LayoutSVGInline {a} at (0,0) size 0x0
-    LayoutSVGText {text} at (97,125) size 102x29 contains 1 chunk(s)
+    LayoutSVGText {text} at (97.25,125.98) size 101.34x27.92 contains 1 chunk(s)
       LayoutSVGInline {a} at (0,0) size 102x28
         LayoutSVGTextPath {textPath} at (0,0) size 102x28
-          LayoutSVGInlineText {#text} at (0,0) size 102x28
+          LayoutSVGInlineText {#text} at (97.25,125.98) size 101.34x27.92
             chunk 1 text run 1 at (102.18,149.56) startOffset 0 endOffset 1 width 4.45: "t"
             chunk 1 text run 2 at (107.84,148.43) startOffset 1 endOffset 2 width 7.10: "e"
             chunk 1 text run 3 at (115.24,146.95) startOffset 2 endOffset 3 width 8.00: "x"
             chunk 1 text run 4 at (121.35,145.73) startOffset 3 endOffset 4 width 4.45: "t"
             chunk 1 text run 5 at (127.89,144.42) startOffset 4 endOffset 5 width 8.90: "P"
             chunk 1 text run 6 at (135.73,142.85) startOffset 5 endOffset 6 width 7.10: "a"
             chunk 1 text run 7 at (141.40,141.72) startOffset 6 endOffset 7 width 4.45: "t"
             chunk 1 text run 8 at (147.50,140.50) startOffset 7 endOffset 8 width 8.00: "h"
             chunk 1 text run 9 at (153.38,140.68) startOffset 8 endOffset 9 width 4.00: " "
             chunk 1 text run 10 at (157.52,141.50) startOffset 9 endOffset 10 width 4.45: "i"
             chunk 1 text run 11 at (163.62,142.72) startOffset 10 endOffset 11 width 8.00: "n"
             chunk 1 text run 12 at (169.51,143.90) startOffset 11 endOffset 12 width 4.00: " "
             chunk 1 text run 13 at (173.65,144.73) startOffset 12 endOffset 13 width 4.45: "l"
             chunk 1 text run 14 at (178.01,145.60) startOffset 13 endOffset 14 width 4.45: "i"
             chunk 1 text run 15 at (184.11,146.82) startOffset 14 endOffset 15 width 8.00: "n"
             chunk 1 text run 16 at (191.95,148.39) startOffset 15 endOffset 16 width 8.00: "k"
     LayoutSVGText {text} at (100,186) size 100x18 contains 1 chunk(s)
       LayoutSVGInline {a} at (0,0) size 100x18
-        LayoutSVGInlineText {#text} at (0,0) size 100x18
+        LayoutSVGInlineText {#text} at (100,186) size 100x18
           chunk 1 text run 1 at (100.00,200.00) startOffset 0 endOffset 15 width 99.98: "ltGlyph content"
-    LayoutSVGText {text} at (100,236) size 134x18 contains 1 chunk(s)
+    LayoutSVGText {text} at (100,236) size 133.33x18 contains 1 chunk(s)
       LayoutSVGTSpan {tspan} at (0,0) size 134x18
         LayoutSVGInline {a} at (0,0) size 134x18
           LayoutSVGTSpan {tspan} at (0,0) size 134x18
-            LayoutSVGInlineText {#text} at (0,0) size 134x18
+            LayoutSVGInlineText {#text} at (100,236) size 133.33x18
               chunk 1 text run 1 at (100.00,250.00) startOffset 0 endOffset 22 width 133.33: "tspan in link in tspan"
-    LayoutSVGText {text}
+    LayoutSVGText {text} at (0,0) size 0x0
       LayoutSVGInline {a} at (0,0) size 0x0