Auto merge of #15302 - andreastt:webdriver-0.20.0, r=Ms2ger

Update to webdriver v0.20.0

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

- [ ] There are tests for these changes OR
- [x] These changes do not require tests because _Servo is not sufficiently mature to run WPT WebDriver tests_

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components/constellation/Cargo.toml

@@ -10,7 +10,7 @@ name = "constellation"
 path = "lib.rs"
 
 [dependencies]
-backtrace = "0.2.1"
+backtrace = "0.3"
 bluetooth_traits = { path = "../bluetooth_traits" }
 canvas = {path = "../canvas"}
 canvas_traits = {path = "../canvas_traits"}

components/servo/Cargo.toml

@@ -21,7 +21,7 @@ clippy = ["plugins/clippy"]
 debugmozjs = ["script/debugmozjs"]
 
 [dependencies]
-backtrace = "0.2"
+backtrace = "0.3"
 bluetooth_traits = {path = "../bluetooth_traits"}
 bluetooth = {path = "../bluetooth"}
 canvas = {path = "../canvas"}

components/webdriver_server/Cargo.toml

@@ -26,4 +26,4 @@ servo_config = {path = "../config", features = ["servo"]}
 servo_url = {path = "../url", features = ["servo"]}
 url = {version = "1.2", features = ["heap_size"]}
 uuid = { version = "0.3.1", features = ["v4"] }
-webdriver = "0.19"
+webdriver = "0.20"

ports/servo/Cargo.toml

@@ -36,7 +36,7 @@ clippy = ["libservo/clippy"]
 debugmozjs = ["libservo/debugmozjs"]
 
 [dependencies]
-backtrace = "0.2"
+backtrace = "0.3"
 browserhtml = {git = "https://github.com/browserhtml/browserhtml", branch = "crate"}
 glutin_app = {path = "../../ports/glutin"}
 log = "0.3"