Auto merge of #16706 - alicemaz:master, r=nox

Bump base64 to 0.4.2

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we have just released a security patch for base64 (preventing integer overflow when sizing a buffer for encoded output). this bumps the version in the three Cargo.toml files that pull it in. there should be no observable difference in behavior, no non-malicious input should be able to trigger this state

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- [x] `./mach test-tidy` does not report any errors
- [ ] These changes fix #__ (github issue number if applicable).

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- [ ] There are tests for these changes OR
- [X] These changes do not require tests because it is a small fix to a dependency with no practical difference in operation from previous.

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components/script/Cargo.toml

@@ -28,7 +28,7 @@ angle = {git = "https://github.com/servo/angle", branch = "servo"}
 app_units = "0.4"
 audio-video-metadata = "0.1.2"
 atomic_refcell = "0.1"
-base64 = "0.4.1"
+base64 = "0.4.2"
 bitflags = "0.7"
 bluetooth_traits = {path = "../bluetooth_traits"}
 byteorder = "1.0"