Add fast/encoding layout tests.

Merged from WebKit at r67178.

The vast majority of these are passing. The exceptions:
- Three Mac-specific tests, won't fix.
- Four failures in the Java HTTP stack (no problem for the Chrome HTTP stack).
- fast/encoding/mailto-always-utf-8 needs a new LayoutTestController callback.

Change-Id: I16c613d42acd0ea2dc146909d514376d0a2e5aaa
diff --git a/LayoutTests/fast/encoding/namespace-tolerance-expected.txt b/LayoutTests/fast/encoding/namespace-tolerance-expected.txt
new file mode 100644
index 0000000..a349969
--- /dev/null
+++ b/LayoutTests/fast/encoding/namespace-tolerance-expected.txt
@@ -0,0 +1,5 @@
+This test ensures a UTF-8 encoding is properly set on documents that: 
+(1) use namespace prefixes on HTML elements 
+(2) specify a non-latin charset 
+(3) contain non-latin characters 
+If this test passes, the UTF-8 character below should exactly match the character the character in namespace-tolerance-expected.txt. 法