Teach Blink's IDL parser to handle defaulted sequences of strings.

LayoutTests/fast/dom/idl-dictionary-unittest-expected.txt

Index: LayoutTests/fast/dom/idl-dictionary-unittest-expected.txt
diff --git a/LayoutTests/fast/dom/idl-dictionary-unittest-expected.txt b/LayoutTests/fast/dom/idl-dictionary-unittest-expected.txt
index 3ca1bbdfd6f97da7204929912086c9fc5b7f3573..7bfe5cb85d8c6b5a9cf08cfef434a31659bb59a0 100644
--- a/LayoutTests/fast/dom/idl-dictionary-unittest-expected.txt
+++ b/LayoutTests/fast/dom/idl-dictionary-unittest-expected.txt
@@ -17,6 +17,7 @@ PASS dict.stringMemberWithDefault is "defaultStringValue"
 PASS dict.byteStringMember is undefined.
 PASS dict.usvStringMember is undefined.
 PASS dict.stringSequenceMember is undefined.
+PASS dict.stringSequenceMemberWithDefault is []
 PASS dict.stringSequenceOrNullMember is undefined.
 PASS dict.elementMember is undefined.
 PASS dict.elementOrNullMember is undefined.
@@ -42,6 +43,7 @@ PASS dict.byteStringMember is undefined.
 PASS dict.usvStringMember is undefined.
 PASS dict.stringMemberWithDefault is "defaultStringValue"
 PASS dict.stringSequenceMember is undefined.
+PASS dict.stringSequenceMemberWithDefault is []
 PASS dict.stringSequenceOrNullMember is undefined.
 PASS dict.elementMember is undefined.
 PASS dict.elementOrNullMember is undefined.
@@ -62,6 +64,7 @@ PASS dict.booleanMember is true
 PASS dict.doubleMember is 3.14
 PASS dict.unrestrictedDoubleMember is NaN
 PASS dict.stringSequenceMember is ["foo", "bar", "baz"]
+PASS dict.stringSequenceMemberWithDefault is ["foo", "bar", "baz"]
 PASS dict.stringSequenceOrNullMember is []
 PASS dict.elementMember is element1
 PASS dict.elementOrNullMember is undefined.
@@ -146,6 +149,7 @@ PASS derived.doubleMember is undefined.
 PASS derived.stringMember is undefined.
 PASS derived.stringMemberWithDefault is "defaultStringValue"
 PASS derived.stringSequenceMember is undefined.
+PASS derived.stringSequenceMemberWithDefault is []
 PASS derived.stringSequenceOrNullMember is undefined.
 PASS derived.elementMember is undefined.
 PASS derived.elementOrNullMember is undefined.