Add a function to escape a query part of url

net/base/escape_unittest.cc

Index: net/base/escape_unittest.cc
diff --git a/net/base/escape_unittest.cc b/net/base/escape_unittest.cc
index 74ae29336d82c2f1ea1379edb196a9b8392b0a1b..4891b08f95a5bc9aff54937ac345572a8f6a9745 100644
--- a/net/base/escape_unittest.cc
+++ b/net/base/escape_unittest.cc
@@ -453,6 +453,24 @@ TEST(EscapeTest, UnescapeForHTML) {
   }
 }
 
+TEST(EscapeTest, EscapeQueryPart) {
+  ASSERT_EQ(
+    // Escaped
+    "%02%0A%1D%20!%22%23$%25&'()*+,-./0123456789:;"
+    "%3C=%3E?@ABCDEFGHIJKLMNOPQRSTUVWXYZ"
+    "%5B%5C%5D%5E_%60abcdefghijklmnopqrstuvwxyz"
+    "%7B%7C%7D~%7F%80%FF",
+    // Most of the character space we care about, un-escaped
+    EscapeQueryPart(
+      "\x02\n\x1d !\"#$%&'()*+,-./0123456789:;"
+      "<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ"
+      "[\\]^_`abcdefghijklmnopqrstuvwxyz"
+      "{|}~\x7f\x80\xff"));
+  ASSERT_EQ("q=a%7Cb%7Cc", EscapeQueryPart("q=a%7Cb%7Cc"));
+  ASSERT_EQ("q=a%7Cb%7Cc", EscapeQueryPart("q=a|b|c"));
+  ASSERT_EQ("q=a%7Cb%7Cc&q2=1%7C2%7C3", EscapeQueryPart("q=a|b|c&q2=1|2|3"));
+}
+
 
 }  // namespace
 }  // namespace net