Reland: Fix setComposingText with empty text when newCursorPosition != 1

content/public/android/javatests/src/org/chromium/content/browser/input/ImeTest.java

Index: content/public/android/javatests/src/org/chromium/content/browser/input/ImeTest.java
diff --git a/content/public/android/javatests/src/org/chromium/content/browser/input/ImeTest.java b/content/public/android/javatests/src/org/chromium/content/browser/input/ImeTest.java
index f2e37c29eebb31345ed0afe4b296c470b9a13d48..0b9135b900a58787f91801ee7910e9ea313d3f94 100644
--- a/content/public/android/javatests/src/org/chromium/content/browser/input/ImeTest.java
+++ b/content/public/android/javatests/src/org/chromium/content/browser/input/ImeTest.java
@@ -188,6 +188,27 @@ public class ImeTest extends ContentShellTestBase {
         waitAndVerifyUpdateSelection(10, 8, 8, 2, 6);
     }
 
+    // When newCursorPosition != 1, setComposingText doesn't work for ReplicaInputConnection
+    // because there is a bug in BaseInputConnection.
+    @CommandLineFlags.Add("enable-features=ImeThread")
+    @SmallTest
+    @Feature({"TextInput", "Main"})
+    public void testSetComposingTextWithEmptyText() throws Throwable {
+        commitText("hello", 1);
+        waitAndVerifyUpdateSelection(0, 5, 5, -1, -1);
+
+        setComposingText("AB", 1);
+        waitAndVerifyUpdateSelection(1, 7, 7, 5, 7);
+
+        // With previous composition.
+        setComposingText("", -3);
+        waitAndVerifyUpdateSelection(2, 2, 2, -1, -1);
+
+        // Without previous composition.
+        setComposingText("", 3);
+        waitAndVerifyUpdateSelection(3, 4, 4, -1, -1);
+    }
+
     @SmallTest
     @Feature({"TextInput", "Main"})
     public void testCommitWhileComposingText() throws Throwable {