Fix Hangul output in iOS and in Safari (#2454)

Correct behaviour for Hangul input under certain circumstances 

Fixes [https://youtrack.jetbrains.com/issue/CMP-8773]

## Testing
`./gradlew testWeb`

## Release Notes
### Fixes - Web
- Mobile. Composite input. When a syllable block is created, a new block
is added instead of replacing the old one

Author: Schahen

compose/ui/ui/src/webCommonW3C/kotlin/androidx/compose/ui/platform/DomInputStrategy.kt

@@ -70,9 +70,7 @@ internal class DomInputStrategy(
                 htmlInput as HTMLElementWithValue
                 val deleteContentBackwardSize = htmlInput.selectionEnd - htmlInput.selectionStart
 
-                if (deleteContentBackwardSize > 0) {
-                    evt.deleteContentBackwardSize = deleteContentBackwardSize
-                }
+                evt.deleteContentBackwardSize = deleteContentBackwardSize
                 nativeInputEventsProcessor.registerEvent(evt)
             }
         })

compose/ui/ui/src/webCommonW3C/kotlin/androidx/compose/ui/platform/NativeInputEventsProcessor.kt

@@ -137,6 +137,10 @@ internal abstract class NativeInputEventsProcessor(
                     val deleteSize = deleteContentBackwardSize
                     if (deleteSize > 0) {
                         add(DeleteSurroundingTextCommand(deleteSize, 0))
+                    } else if (deleteSize == 0) {
+                        // under specific circumstance previous symbol can be deleted while inputing new one
+                        // see https://youtrack.jetbrains.com/issue/CMP-8773
+                        add(BackspaceCommand())
                     }
                 }
             }

…ui/input/specs/СompositeInputTestSpec.kt …ui/input/specs/CompositeInputTestSpec.ktcompose/ui/ui/src/webTest/kotlin/androidx/compose/ui/input/specs/СompositeInputTestSpec.kt renamed to compose/ui/ui/src/webTest/kotlin/androidx/compose/ui/input/specs/CompositeInputTestSpec.kt compose/ui/ui/src/webTest/kotlin/androidx/compose/ui/input/specs/СompositeInputTestSpec.kt renamed to compose/ui/ui/src/webTest/kotlin/androidx/compose/ui/input/specs/CompositeInputTestSpec.kt

@@ -26,6 +26,7 @@ import androidx.compose.ui.events.keyEvent
 import kotlin.test.Test
 import kotlin.test.assertIs
 import org.w3c.dom.HTMLTextAreaElement
+import androidx.compose.ui.platform.InputEvent as InputEventDetailed
 
 internal interface СompositeInputTestSpec : TextFieldTestSpec {
 
@@ -77,6 +78,26 @@ internal interface ChromeCompositeInput : СompositeInputTestSpec {
             keyEvent(compositionInput, type = "keyup")
         )
     }
+
+    @Test
+    fun `input hangul-hol`() = runApplicationTest {
+        val textFieldValue = createApplicationWithHolder()
+        eventsSequence(
+            compositionStart(),
+            keyEvent(key= "ㅎ", code = "KeyG", keyCode = 229),
+            beforeInput(inputType = "compositionStart", data = "null"),
+            keyEvent(key= "ㅎ", code = "KeyG", keyCode = 71, type = "keyup", isComposing = true),
+            keyEvent(key= "ㅗ", code = "KeyH", keyCode = 229),
+            beforeInput(inputType = "insertCompositionText", data = "호"),
+            keyEvent(key= "ㅗ", code = "KeyH", keyCode = 72, type = "keyup", isComposing = true),
+            keyEvent(key= "ㄹ", code = "KeyF", keyCode = 229),
+            beforeInput(inputType = "insertCompositionText", data = "홀"),
+            keyEvent(key= "ㄹ", code = "KeyF", keyCode = 70, type = "keyup", isComposing = true),
+        ).sendToHtmlInput()
+
+        textFieldValue.awaitAndAssertTextEquals("홀")
+    }
+
 }
 
 internal interface FirefoxCompositeInput : СompositeInputTestSpec {
@@ -147,7 +168,7 @@ internal interface WinCompositeInput : СompositeInputTestSpec {
     }
 
     @Test
-    fun `input korean-hol`() = runApplicationTest {
+    fun `input hangul-hol`() = runApplicationTest {
         val textFieldValue = createApplicationWithHolder()
         compositionStart("g", "ㅎ")
             .compositionUpdate("h", "호")
@@ -216,6 +237,26 @@ internal interface IosCompositeInput : СompositeInputTestSpec {
             compositionEnd(typedKey),
         )
     }
+
+    @Test
+    fun `input hangul-hol`() = runApplicationTest {
+        val textFieldValue = createApplicationWithHolder()
+        eventsSequence(
+            keyEvent(key= "ㅎ", code = "Unidentified", keyCode = 0),
+            beforeInput("insertText", data = "ㅎ", isComposing = false),
+            keyEvent(key= "ㅎ", code = "Unidentified", keyCode = 0, type = "keyup"),
+            keyEvent(key= "ㅗ", code = "Unidentified", keyCode = 0),
+            beforeInput("deleteContentBackward", data = null, isComposing = false),
+            beforeInput("insertText", data = "호", isComposing = false),
+            keyEvent(key= "ㅗ", code = "Unidentified", keyCode = 0, type = "keyup"),
+            keyEvent(key= "ㄹ", code = "Unidentified", keyCode = 0),
+            beforeInput("deleteContentBackward", data = null, isComposing = false),
+            beforeInput("insertText", data = "홀", isComposing = false),
+            keyEvent(key= "ㄹ", code = "Unidentified", keyCode = 0, type = "keyup")
+        ).sendToHtmlInput()
+
+        textFieldValue.awaitAndAssertTextEquals("홀")
+    }
 }
 
 internal interface AndroidCompositeInput : СompositeInputTestSpec {
@@ -252,7 +293,7 @@ internal interface AndroidCompositeInput : СompositeInputTestSpec {
     }
 
     @Test
-    fun `input korean-hol`() = runApplicationTest {
+    fun `input hangul-hol`() = runApplicationTest {
         val textFieldValue = createApplicationWithHolder()
         compositionStart("g", "ㅎ")
             .compositionUpdate("h", "호")