Auto merge of #22133 - servo:extern-crate, r=SimonSapin

Use 2018-edition idioms in crates that use that edition

The first commit is almost entirely mechanical, created by running `cargo fix --edition-idioms` and relevant crates. I undid the change of adding an anonymous lifetime parameter in types that have implicit lifetimes parameters, for example replacing `&mut Formatter` with `&mut Formatter<'_>`, because I don’t like it. The remaining changes are, in many places:

* Add `dyn` to trait object types, for example `Rc<gl::Gl>` to `Rc<dyn gl::Gl>`. This change also works in the 2015 edition.
* Remove `extern crate` where is it made unneeded by changes to the import/module system.

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1 files changed, 17 insertions, 17 deletions

diff --git a/components/bluetooth/test.rs b/components/bluetooth/test.rs
index 6138bbdb35e..0056f06767c 100644
--- a/components/bluetooth/test.rs
+++ b/components/bluetooth/test.rs
@@ -137,7 +137,7 @@ fn generate_id() -> Uuid {
 }
 
 // Set the adapter's name, is_powered and is_discoverable attributes
-fn set_adapter(adapter: &BluetoothAdapter, adapter_name: String) -> Result<(), Box<Error>> {
+fn set_adapter(adapter: &BluetoothAdapter, adapter_name: String) -> Result<(), Box<dyn Error>> {
     adapter.set_name(adapter_name)?;
     adapter.set_powered(true)?;
     adapter.set_discoverable(true)?;
@@ -149,7 +149,7 @@ fn create_device(
     adapter: &BluetoothAdapter,
     name: String,
     address: String,
-) -> Result<BluetoothDevice, Box<Error>> {
+) -> Result<BluetoothDevice, Box<dyn Error>> {
     let device = BluetoothDevice::create_mock_device(adapter.clone(), generate_id().to_string())?;
     device.set_name(Some(name))?;
     device.set_address(address)?;
@@ -163,7 +163,7 @@ fn create_device_with_uuids(
     name: String,
     address: String,
     uuids: Vec<String>,
-) -> Result<BluetoothDevice, Box<Error>> {
+) -> Result<BluetoothDevice, Box<dyn Error>> {
     let device = create_device(adapter, name, address)?;
     device.set_uuids(uuids)?;
     Ok(device)
@@ -173,7 +173,7 @@ fn create_device_with_uuids(
 fn create_service(
     device: &BluetoothDevice,
     uuid: String,
-) -> Result<BluetoothGATTService, Box<Error>> {
+) -> Result<BluetoothGATTService, Box<dyn Error>> {
     let service =
         BluetoothGATTService::create_mock_service(device.clone(), generate_id().to_string())?;
     service.set_uuid(uuid)?;
@@ -184,7 +184,7 @@ fn create_service(
 fn create_characteristic(
     service: &BluetoothGATTService,
     uuid: String,
-) -> Result<BluetoothGATTCharacteristic, Box<Error>> {
+) -> Result<BluetoothGATTCharacteristic, Box<dyn Error>> {
     let characteristic = BluetoothGATTCharacteristic::create_mock_characteristic(
         service.clone(),
         generate_id().to_string(),
@@ -198,7 +198,7 @@ fn create_characteristic_with_value(
     service: &BluetoothGATTService,
     uuid: String,
     value: Vec<u8>,
-) -> Result<BluetoothGATTCharacteristic, Box<Error>> {
+) -> Result<BluetoothGATTCharacteristic, Box<dyn Error>> {
     let characteristic = create_characteristic(service, uuid)?;
     characteristic.set_value(value)?;
     Ok(characteristic)
@@ -208,7 +208,7 @@ fn create_characteristic_with_value(
 fn create_descriptor(
     characteristic: &BluetoothGATTCharacteristic,
     uuid: String,
-) -> Result<BluetoothGATTDescriptor, Box<Error>> {
+) -> Result<BluetoothGATTDescriptor, Box<dyn Error>> {
     let descriptor = BluetoothGATTDescriptor::create_mock_descriptor(
         characteristic.clone(),
         generate_id().to_string(),
@@ -222,7 +222,7 @@ fn create_descriptor_with_value(
     characteristic: &BluetoothGATTCharacteristic,
     uuid: String,
     value: Vec<u8>,
-) -> Result<BluetoothGATTDescriptor, Box<Error>> {
+) -> Result<BluetoothGATTDescriptor, Box<dyn Error>> {
     let descriptor = create_descriptor(characteristic, uuid)?;
     descriptor.set_value(value)?;
     Ok(descriptor)
@@ -231,7 +231,7 @@ fn create_descriptor_with_value(
 fn create_heart_rate_service(
     device: &BluetoothDevice,
     empty: bool,
-) -> Result<BluetoothGATTService, Box<Error>> {
+) -> Result<BluetoothGATTService, Box<dyn Error>> {
     // Heart Rate Service
     let heart_rate_service = create_service(device, HEART_RATE_SERVICE_UUID.to_owned())?;
 
@@ -274,7 +274,7 @@ fn create_heart_rate_service(
 fn create_generic_access_service(
     device: &BluetoothDevice,
     empty: bool,
-) -> Result<BluetoothGATTService, Box<Error>> {
+) -> Result<BluetoothGATTService, Box<dyn Error>> {
     // Generic Access Service
     let generic_access_service = create_service(device, GENERIC_ACCESS_SERVICE_UUID.to_owned())?;
 
@@ -335,7 +335,7 @@ fn create_generic_access_service(
 fn create_heart_rate_device(
     adapter: &BluetoothAdapter,
     empty: bool,
-) -> Result<BluetoothDevice, Box<Error>> {
+) -> Result<BluetoothDevice, Box<dyn Error>> {
     // Heart Rate Device
     let heart_rate_device = create_device_with_uuids(
         adapter,
@@ -362,7 +362,7 @@ fn create_heart_rate_device(
 
 fn create_missing_characterisitc_heart_rate_device(
     adapter: &BluetoothAdapter,
-) -> Result<(), Box<Error>> {
+) -> Result<(), Box<dyn Error>> {
     let heart_rate_device_empty = create_heart_rate_device(adapter, true)?;
 
     let _generic_access_service_empty =
@@ -375,7 +375,7 @@ fn create_missing_characterisitc_heart_rate_device(
 
 fn create_missing_descriptor_heart_rate_device(
     adapter: &BluetoothAdapter,
-) -> Result<(), Box<Error>> {
+) -> Result<(), Box<dyn Error>> {
     let heart_rate_device_empty = create_heart_rate_device(adapter, true)?;
 
     let generic_access_service_empty =
@@ -399,7 +399,7 @@ fn create_missing_descriptor_heart_rate_device(
     Ok(())
 }
 
-fn create_two_heart_rate_services_device(adapter: &BluetoothAdapter) -> Result<(), Box<Error>> {
+fn create_two_heart_rate_services_device(adapter: &BluetoothAdapter) -> Result<(), Box<dyn Error>> {
     let heart_rate_device_empty = create_heart_rate_device(adapter, true)?;
 
     heart_rate_device_empty.set_uuids(vec![
@@ -435,7 +435,7 @@ fn create_two_heart_rate_services_device(adapter: &BluetoothAdapter) -> Result<(
     Ok(())
 }
 
-fn create_blocklisted_device(adapter: &BluetoothAdapter) -> Result<(), Box<Error>> {
+fn create_blocklisted_device(adapter: &BluetoothAdapter) -> Result<(), Box<dyn Error>> {
     let connectable_device = create_device_with_uuids(
         adapter,
         CONNECTABLE_DEVICE_NAME.to_owned(),
@@ -490,7 +490,7 @@ fn create_blocklisted_device(adapter: &BluetoothAdapter) -> Result<(), Box<Error
     Ok(())
 }
 
-fn create_glucose_heart_rate_devices(adapter: &BluetoothAdapter) -> Result<(), Box<Error>> {
+fn create_glucose_heart_rate_devices(adapter: &BluetoothAdapter) -> Result<(), Box<dyn Error>> {
     let glucose_devie = create_device_with_uuids(
         adapter,
         GLUCOSE_DEVICE_NAME.to_owned(),
@@ -517,7 +517,7 @@ fn create_glucose_heart_rate_devices(adapter: &BluetoothAdapter) -> Result<(), B
     Ok(())
 }
 
-pub fn test(manager: &mut BluetoothManager, data_set_name: String) -> Result<(), Box<Error>> {
+pub fn test(manager: &mut BluetoothManager, data_set_name: String) -> Result<(), Box<dyn Error>> {
     let may_existing_adapter = manager.get_or_create_adapter();
     let adapter = match may_existing_adapter.as_ref() {
         Some(adapter) => adapter,