Auto merge of #11192 - perlun:remove-unused-imports, r=Manishearth

Removed unused imports

- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix #11185
- [X] These changes do not require tests because it only removes dead code.

----

This fixes #11185.

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1 files changed, 0 insertions, 1 deletions

diff --git a/components/script/dom/htmliframeelement.rs b/components/script/dom/htmliframeelement.rs
index b3bc303b8b2..d31c8a09484 100644
--- a/components/script/dom/htmliframeelement.rs
+++ b/components/script/dom/htmliframeelement.rs
@@ -38,7 +38,6 @@ use msg::constellation_msg::{NavigationDirection, PipelineId, SubpageId};
 use net_traits::response::HttpsState;
 use script_traits::IFrameSandboxState::{IFrameSandboxed, IFrameUnsandboxed};
 use script_traits::{IFrameLoadInfo, MozBrowserEvent, ScriptMsg as ConstellationMsg};
-use std::ascii::AsciiExt;
 use std::cell::Cell;
 use string_cache::Atom;
 use style::context::ReflowGoal;