[css3-text] Implement text-decoration property shorthand

LayoutTests/inspector/styles/styles-new-API-expected.txt

 Tests that InspectorCSSAgent API methods work as expected.
 
 H1
 
 
 === Computed style property count for body ===
 OK
 
 === Matched rules for body ===
 body: [user-agent] {
@@ skipping 33 matching lines @@
     ['background-position-x':'initial' is-important] @[undefined-undefined] style
     ['background-position-y':'initial' is-important] @[undefined-undefined] style
     ['background-origin':'initial' is-important] @[undefined-undefined] style
     ['background-clip':'initial' is-important] @[undefined-undefined] style
     ['background-color':'green' is-important] @[undefined-undefined] style
     ['background-size':'initial' is-important] @[undefined-undefined] style
 }
 body.mainpage: [regular, 3:0-3:13] {
     ['text-decoration':'none'] @[4:4-4:26] active
     ['badproperty':'1badvalue1' non-parsed] @[5:5-5:29] active
+    ['text-decoration-line':'none'] @[undefined-undefined] style
+    ['text-decoration-style':'initial'] @[undefined-undefined] style
+    ['text-decoration-color':'initial'] @[undefined-undefined] style
 }
 body.mainpage: [regular, 8:0-8:13] {
     ['prop1':'val1' non-parsed] @[9:4-9:16] active
     ['prop2':'val2' non-parsed] @[10:4-10:16] active
 }
 
 === Pseudo rules for body ===
 PseudoId=4
 body::after: [regular, 26:0-26:11] {
     ['content':'"After body"'] @[27:4-27:26] active
@@ skipping 51 matching lines @@
     ['background-position-x':'initial' is-important] @[undefined-undefined] style
     ['background-position-y':'initial' is-important] @[undefined-undefined] style
     ['background-origin':'initial' is-important] @[undefined-undefined] style
     ['background-clip':'initial' is-important] @[undefined-undefined] style
     ['background-color':'green' is-important] @[undefined-undefined] style
     ['background-size':'initial' is-important] @[undefined-undefined] style
 }
 body.mainpage: [regular, 3:0-3:13] {
     ['text-decoration':'none'] @[4:4-4:26] active
     ['badproperty':'1badvalue1' non-parsed] @[5:5-5:29] active
+    ['text-decoration-line':'none'] @[undefined-undefined] style
+    ['text-decoration-style':'initial'] @[undefined-undefined] style
+    ['text-decoration-color':'initial'] @[undefined-undefined] style
 }
 body.mainpage: [regular, 8:0-8:13] {
     ['prop1':'val1' non-parsed] @[9:4-9:16] active
     ['prop2':'val2' non-parsed] @[10:4-10:16] active
 }
 body:hover: [regular, 13:0-13:10] {
     ['color':'#CDE'] @[14:2-14:14] active
 }
 
 === Attributes style for table ===
@@ skipping 180 matching lines @@
     prop2: val2;
 }
 
 body:hover {
   color: #CDE;
 }
 '
 body.mainpage: [regular, 3:0-3:13] {
     ['text-decoration':'none'] @[4:4-4:26] active
     ['badproperty':'1badvalue1' non-parsed] @[5:5-5:29] active
+    ['text-decoration-line':'none'] @[undefined-undefined] style
+    ['text-decoration-style':'initial'] @[undefined-undefined] style
+    ['text-decoration-color':'initial'] @[undefined-undefined] style
 }
 body.mainpage: [regular, 8:0-8:13] {
     ['prop1':'val1' non-parsed] @[9:4-9:16] active
     ['prop2':'val2' non-parsed] @[10:4-10:16] active
 }
 body:hover: [regular, 13:0-13:10] {
     ['color':'#CDE'] @[14:2-14:14] active
 }
 
 === Last stylesheet patched ===
@@ skipping 153 matching lines @@
 ['border-top-color':'initial'] @[undefined-undefined] style
 ['border-right-color':'initial'] @[undefined-undefined] style
 ['border-bottom-color':'initial'] @[undefined-undefined] style
 ['border-left-color':'initial'] @[undefined-undefined] style
 ['border-image-source':'initial'] @[undefined-undefined] style
 ['border-image-slice':'initial'] @[undefined-undefined] style
 ['border-image-width':'initial'] @[undefined-undefined] style
 ['border-image-outset':'initial'] @[undefined-undefined] style
 ['border-image-repeat':'initial'] @[undefined-undefined] style