Create a top-level "third_party" directory

This directory now contains third_party software that is vendored into
the Servo source tree. The idea is that it would eventually hold
webrender and other crates from mozilla-central as well with a standard
patch management approach for each.

third_party/WebIDL/tests/test_extended_attributes.py

@@ -0,0 +1,131 @@
+import WebIDL
+
+
+def WebIDLTest(parser, harness):
+    parser.parse(
+        """
+        [LegacyNoInterfaceObject]
+        interface TestExtendedAttr {
+          [LegacyUnforgeable] readonly attribute byte b;
+        };
+    """
+    )
+
+    results = parser.finish()
+
+    parser = parser.reset()
+    parser.parse(
+        """
+        [Pref="foo.bar",Pref=flop]
+        interface TestExtendedAttr {
+          [Pref="foo.bar"] attribute byte b;
+        };
+    """
+    )
+
+    results = parser.finish()
+
+    parser = parser.reset()
+    parser.parse(
+        """
+        interface TestLegacyLenientThis {
+          [LegacyLenientThis] attribute byte b;
+        };
+    """
+    )
+
+    results = parser.finish()
+    harness.ok(
+        results[0].members[0].hasLegacyLenientThis(), "Should have a lenient this"
+    )
+
+    parser = parser.reset()
+    threw = False
+    try:
+        parser.parse(
+            """
+            interface TestLegacyLenientThis2 {
+              [LegacyLenientThis=something] attribute byte b;
+            };
+        """
+        )
+        results = parser.finish()
+    except:
+        threw = True
+
+    harness.ok(threw, "[LegacyLenientThis] must take no arguments")
+
+    parser = parser.reset()
+    parser.parse(
+        """
+        interface TestClamp {
+          undefined testClamp([Clamp] long foo);
+          undefined testNotClamp(long foo);
+        };
+    """
+    )
+
+    results = parser.finish()
+    # Pull out the first argument out of the arglist of the first (and
+    # only) signature.
+    harness.ok(
+        results[0].members[0].signatures()[0][1][0].type.hasClamp(), "Should be clamped"
+    )
+    harness.ok(
+        not results[0].members[1].signatures()[0][1][0].type.hasClamp(),
+        "Should not be clamped",
+    )
+
+    parser = parser.reset()
+    threw = False
+    try:
+        parser.parse(
+            """
+            interface TestClamp2 {
+              undefined testClamp([Clamp=something] long foo);
+            };
+        """
+        )
+        results = parser.finish()
+    except:
+        threw = True
+
+    harness.ok(threw, "[Clamp] must take no arguments")
+
+    parser = parser.reset()
+    parser.parse(
+        """
+        interface TestEnforceRange {
+          undefined testEnforceRange([EnforceRange] long foo);
+          undefined testNotEnforceRange(long foo);
+        };
+    """
+    )
+
+    results = parser.finish()
+    # Pull out the first argument out of the arglist of the first (and
+    # only) signature.
+    harness.ok(
+        results[0].members[0].signatures()[0][1][0].type.hasEnforceRange(),
+        "Should be enforceRange",
+    )
+    harness.ok(
+        not results[0].members[1].signatures()[0][1][0].type.hasEnforceRange(),
+        "Should not be enforceRange",
+    )
+
+    parser = parser.reset()
+    threw = False
+    try:
+        parser.parse(
+            """
+            interface TestEnforceRange2 {
+              undefined testEnforceRange([EnforceRange=something] long foo);
+            };
+        """
+        )
+        results = parser.finish()
+    except:
+        threw = True
+
+    harness.ok(threw, "[EnforceRange] must take no arguments")