Auto merge of #13701 - Manishearth:nsstring, r=emilio,mystor

Vendor nsstring bindings, use for text-overflow

From [bug 1309165](https://bugzilla.mozilla.org/show_bug.cgi?id=1309165)

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components/style/Cargo.toml

@@ -13,7 +13,7 @@ path = "lib.rs"
 doctest = false
 
 [features]
-gecko = []
+gecko = ["nsstring_vendor"]
 servo = ["serde/unstable", "serde", "serde_derive", "heapsize_plugin",
          "style_traits/servo", "app_units/plugins",
          "cssparser/heap_size", "cssparser/serde-serialization",
@@ -36,6 +36,7 @@ lazy_static = "0.2"
 log = "0.3.5"
 libc = "0.2"
 matches = "0.1"
+nsstring_vendor = {path = "gecko_bindings/nsstring_vendor", optional = true}
 num-integer = "0.1.32"
 num-traits = "0.1.32"
 num_cpus = "0.2.2"

components/style/binding_tools/regen.py

@@ -68,7 +68,9 @@
         "raw_lines": [
             # We can get rid of this when the bindings move into the style crate.
             "pub enum OpaqueStyleData {}",
+            "pub use nsstring::nsStringRepr as nsString;"
         ],
+        "blacklist_types": ["nsString"],
         "whitelist_vars": [
             "NS_THEME_.*",
             "NODE_.*",
@@ -426,6 +428,11 @@ def zero_size_type(ty, flags):
             flags.append("--opaque-type")
             flags.append(ty)
 
+    if "blacklist_types" in current_target:
+        for ty in current_target["blacklist_types"]:
+            flags.append("--blacklist-type")
+            flags.append(ty)
+
     if "servo_nullable_arc_types" in current_target:
         for ty in current_target["servo_nullable_arc_types"]:
             flags.append("--blacklist-type")

components/style/gecko_bindings/nsstring_vendor/Cargo.toml

@@ -0,0 +1,12 @@
+[package]
+name = "nsstring_vendor"
+version = "0.1.0"
+authors = ["nobody@mozilla.com"]
+license = "MPL-2.0"
+description = "Rust bindings to xpcom string types"
+
+
+# Revendoring nsstring from m-c into Servo
+
+[dependencies]
+