Fixes platform_channel sample (#1982)

Adds the AccelerometerStreamHandler to Runner. For some reason, the
reference of file was not included in project.pbxproj.

Fixes: #1981 

## Pre-launch Checklist

- [x] I read the [Flutter Style Guide] _recently_, and have followed its
advice.
- [x] I signed the [CLA].
- [x] I read the [Contributors Guide].
- [x] I updated/added relevant documentation (doc comments with `///`).
- [x] All existing and new tests are passing.

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channel on [Discord].

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[CLA]: https://cla.developers.google.com/
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[Contributors Guide]:
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platform_channels/ios/Runner.xcodeproj/project.pbxproj

@@ -8,12 +8,13 @@
 
 /* Begin PBXBuildFile section */
 		1498D2341E8E89220040F4C2 /* GeneratedPluginRegistrant.m in Sources */ = {isa = PBXBuildFile; fileRef = 1498D2331E8E89220040F4C2 /* GeneratedPluginRegistrant.m */; };
+		1C5D8C2F2A8127190006C60D /* AccelerometerStreamHandler.swift in Sources */ = {isa = PBXBuildFile; fileRef = 1C5D8C2E2A8127190006C60D /* AccelerometerStreamHandler.swift */; };
+		331C808B294A63AB00263BE5 /* RunnerTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = 331C807B294A618700263BE5 /* RunnerTests.swift */; };
 		3B3967161E833CAA004F5970 /* AppFrameworkInfo.plist in Resources */ = {isa = PBXBuildFile; fileRef = 3B3967151E833CAA004F5970 /* AppFrameworkInfo.plist */; };
 		74858FAF1ED2DC5600515810 /* AppDelegate.swift in Sources */ = {isa = PBXBuildFile; fileRef = 74858FAE1ED2DC5600515810 /* AppDelegate.swift */; };
 		97C146FC1CF9000F007C117D /* Main.storyboard in Resources */ = {isa = PBXBuildFile; fileRef = 97C146FA1CF9000F007C117D /* Main.storyboard */; };
 		97C146FE1CF9000F007C117D /* Assets.xcassets in Resources */ = {isa = PBXBuildFile; fileRef = 97C146FD1CF9000F007C117D /* Assets.xcassets */; };
 		97C147011CF9000F007C117D /* LaunchScreen.storyboard in Resources */ = {isa = PBXBuildFile; fileRef = 97C146FF1CF9000F007C117D /* LaunchScreen.storyboard */; };
-		331C808B294A63AB00263BE5 /* RunnerTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = 331C807B294A618700263BE5 /* RunnerTests.swift */; };
 /* End PBXBuildFile section */
 
 /* Begin PBXContainerItemProxy section */
@@ -42,6 +43,9 @@
 /* Begin PBXFileReference section */
 		1498D2321E8E86230040F4C2 /* GeneratedPluginRegistrant.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = GeneratedPluginRegistrant.h; sourceTree = "<group>"; };
 		1498D2331E8E89220040F4C2 /* GeneratedPluginRegistrant.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = GeneratedPluginRegistrant.m; sourceTree = "<group>"; };
+		1C5D8C2E2A8127190006C60D /* AccelerometerStreamHandler.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = AccelerometerStreamHandler.swift; sourceTree = "<group>"; };
+		331C807B294A618700263BE5 /* RunnerTests.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = RunnerTests.swift; sourceTree = "<group>"; };
+		331C8081294A63A400263BE5 /* RunnerTests.xctest */ = {isa = PBXFileReference; explicitFileType = wrapper.cfbundle; includeInIndex = 0; path = RunnerTests.xctest; sourceTree = BUILT_PRODUCTS_DIR; };
 		3B3967151E833CAA004F5970 /* AppFrameworkInfo.plist */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text.plist.xml; name = AppFrameworkInfo.plist; path = Flutter/AppFrameworkInfo.plist; sourceTree = "<group>"; };
 		74858FAD1ED2DC5600515810 /* Runner-Bridging-Header.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = "Runner-Bridging-Header.h"; sourceTree = "<group>"; };
 		74858FAE1ED2DC5600515810 /* AppDelegate.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = AppDelegate.swift; sourceTree = "<group>"; };
@@ -53,8 +57,6 @@
 		97C146FD1CF9000F007C117D /* Assets.xcassets */ = {isa = PBXFileReference; lastKnownFileType = folder.assetcatalog; path = Assets.xcassets; sourceTree = "<group>"; };
 		97C147001CF9000F007C117D /* Base */ = {isa = PBXFileReference; lastKnownFileType = file.storyboard; name = Base; path = Base.lproj/LaunchScreen.storyboard; sourceTree = "<group>"; };
 		97C147021CF9000F007C117D /* Info.plist */ = {isa = PBXFileReference; lastKnownFileType = text.plist.xml; path = Info.plist; sourceTree = "<group>"; };
-		331C807B294A618700263BE5 /* RunnerTests.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = RunnerTests.swift; sourceTree = "<group>"; };
-		331C8081294A63A400263BE5 /* RunnerTests.xctest */ = {isa = PBXFileReference; explicitFileType = wrapper.cfbundle; includeInIndex = 0; path = RunnerTests.xctest; sourceTree = BUILT_PRODUCTS_DIR; };
 /* End PBXFileReference section */
 
 /* Begin PBXFrameworksBuildPhase section */
@@ -68,6 +70,14 @@
 /* End PBXFrameworksBuildPhase section */
 
 /* Begin PBXGroup section */
+		331C8082294A63A400263BE5 /* RunnerTests */ = {
+			isa = PBXGroup;
+			children = (
+				331C807B294A618700263BE5 /* RunnerTests.swift */,
+			);
+			path = RunnerTests;
+			sourceTree = "<group>";
+		};
 		9740EEB11CF90186004384FC /* Flutter */ = {
 			isa = PBXGroup;
 			children = (
@@ -79,14 +89,6 @@
 			name = Flutter;
 			sourceTree = "<group>";
 		};
-		331C8082294A63A400263BE5 /* RunnerTests */ = {
-			isa = PBXGroup;
-			children = (
-				331C807B294A618700263BE5 /* RunnerTests.swift */,
-			);
-			path = RunnerTests;
-			sourceTree = "<group>";
-		};
 		97C146E51CF9000F007C117D = {
 			isa = PBXGroup;
 			children = (
@@ -109,6 +111,7 @@
 		97C146F01CF9000F007C117D /* Runner */ = {
 			isa = PBXGroup;
 			children = (
+				1C5D8C2E2A8127190006C60D /* AccelerometerStreamHandler.swift */,
 				97C146FA1CF9000F007C117D /* Main.storyboard */,
 				97C146FD1CF9000F007C117D /* Assets.xcassets */,
 				97C146FF1CF9000F007C117D /* LaunchScreen.storyboard */,
@@ -129,7 +132,6 @@
 			buildConfigurationList = 331C8087294A63A400263BE5 /* Build configuration list for PBXNativeTarget "RunnerTests" */;
 			buildPhases = (
 				331C807D294A63A400263BE5 /* Sources */,
-				331C807E294A63A400263BE5 /* Frameworks */,
 				331C807F294A63A400263BE5 /* Resources */,
 			);
 			buildRules = (
@@ -270,6 +272,7 @@
 			files = (
 				74858FAF1ED2DC5600515810 /* AppDelegate.swift in Sources */,
 				1498D2341E8E89220040F4C2 /* GeneratedPluginRegistrant.m in Sources */,
+				1C5D8C2F2A8127190006C60D /* AccelerometerStreamHandler.swift in Sources */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 		};
@@ -376,7 +379,6 @@
 		};
 		331C8088294A63A400263BE5 /* Debug */ = {
 			isa = XCBuildConfiguration;
-			baseConfigurationReference = AE0B7B92F70575B8D7E0D07E /* Pods-RunnerTests.debug.xcconfig */;
 			buildSettings = {
 				BUNDLE_LOADER = "$(TEST_HOST)";
 				CODE_SIGN_STYLE = Automatic;
@@ -394,7 +396,6 @@
 		};
 		331C8089294A63A400263BE5 /* Release */ = {
 			isa = XCBuildConfiguration;
-			baseConfigurationReference = 89B67EB44CE7B6631473024E /* Pods-RunnerTests.release.xcconfig */;
 			buildSettings = {
 				BUNDLE_LOADER = "$(TEST_HOST)";
 				CODE_SIGN_STYLE = Automatic;
@@ -410,7 +411,6 @@
 		};
 		331C808A294A63A400263BE5 /* Profile */ = {
 			isa = XCBuildConfiguration;
-			baseConfigurationReference = 640959BDD8F10B91D80A66BE /* Pods-RunnerTests.profile.xcconfig */;
 			buildSettings = {
 				BUNDLE_LOADER = "$(TEST_HOST)";
 				CODE_SIGN_STYLE = Automatic;