Auto merge of #543 - antrik:update-ipc_channel, r=glennw

Update `ipc-channel` dependency to 0.6

Doing a tree-wide update, mostly to make sure nobody accidentally breaks
the new interface, where `ipc_channel::Sender` is no longer `Sync`.

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webrender/Cargo.toml

@@ -18,7 +18,7 @@ byteorder = "0.5"
 euclid = "0.10"
 fnv="1.0"
 gleam = "0.2"
-ipc-channel = "0.5"
+ipc-channel = "0.6"
 lazy_static = "0.2"
 log = "0.3"
 num-traits = "0.1.32"

webrender_traits/Cargo.toml

@@ -21,7 +21,7 @@ heapsize = "0.3.6"
 offscreen_gl_context = {version = "0.4.5", features = ["serde_serialization"]}
 serde = "0.8"
 serde_derive = {version = "0.8", optional = true}
-ipc-channel = "0.5.0"
+ipc-channel = "0.6"
 
 [target.x86_64-apple-darwin.dependencies]
 core-graphics = "0.4"