Remove third_party/golang.org/x/mobile as it is no longer used with Go 1.5.

third_party/go/src/golang.org/x/mobile/bind/seq/utf16_test.go

Index: third_party/go/src/golang.org/x/mobile/bind/seq/utf16_test.go
diff --git a/third_party/go/src/golang.org/x/mobile/bind/seq/utf16_test.go b/third_party/go/src/golang.org/x/mobile/bind/seq/utf16_test.go
deleted file mode 100644
index e4527374a88099dbff75aca1dd9a5d5478cc6c51..0000000000000000000000000000000000000000
--- a/third_party/go/src/golang.org/x/mobile/bind/seq/utf16_test.go
+++ /dev/null
@@ -1,39 +0,0 @@
-// Copyright 2014 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package seq
-
-import "testing"
-
-var utf16Tests = []string{
-	"abcxyz09{}",
-	"Hello, 世界",
-	string([]rune{0xffff, 0x10000, 0x10001, 0x12345, 0x10ffff}),
-}
-
-func TestUTF16(t *testing.T) {
-	for _, test := range utf16Tests {
-		buf := new(Buffer)
-		buf.WriteUTF16(test)
-		buf.Offset = 0
-		got := buf.ReadUTF16()
-		if got != test {
-			t.Errorf("got %q, want %q", got, test)
-		}
-	}
-}
-
-func TestSequential(t *testing.T) {
-	buf := new(Buffer)
-	for _, test := range utf16Tests {
-		buf.WriteUTF16(test)
-	}
-	buf.Offset = 0
-	for i, test := range utf16Tests {
-		got := buf.ReadUTF16()
-		if got != test {
-			t.Errorf("%d: got %q, want %q", i, got, test)
-		}
-	}
-}