[camerax] Correct assumption about preview being correctly rotated by default on API 29 (flutter#7714)

Changes assumption about camera preview being automatically corrected by CameraX on API <= 29 to API < 29 based on the fact that an `ImageReader` backs devices running API 29+, on which the camera preview will not automatically be corrected by CameraX. 

Related to flutter/flutter#154241.

Author: camsim99

packages/camera/camera_android_camerax/CHANGELOG.md

@@ -1,3 +1,9 @@
+## 0.6.9
+
+* Corrects assumption about automatic preview correction happening on API >= 29 to API > 29,
+  based on the fact that the `ImageReader` Impeller backend is not used for the most part on
+  devices running API 29+.
+
 ## 0.6.8+3
 
 * Removes dependency on org.jetbrains.kotlin:kotlin-bom.

packages/camera/camera_android_camerax/android/src/main/java/io/flutter/plugins/camerax/SystemServicesHostApiImpl.java

@@ -106,16 +106,16 @@ public String getTempFilePath(@NonNull String prefix, @NonNull String suffix) {
   }
 
   /**
-   * Returns whether or not a {@code SurfaceTexture} backs the {@code Surface} provided to CameraX
-   * to build the camera preview. If it is backed by a {@code Surface}, then the transformation
-   * needed to correctly rotate the preview has already been applied.
+   * Returns whether or not Impeller uses an {@code ImageReader} backend to provide a {@code
+   * Surface} to CameraX to build the preview. If it is backed by an {@code ImageReader}, then
+   * CameraX will not automatically apply the transformation needed to correct the preview.
    *
-   * <p>This is determined by the engine, who uses {@code SurfaceTexture}s on Android SDKs 29 and
-   * below.
+   * <p>This is determined by the engine, which approximately uses {@code SurfaceTexture}s on
+   * Android SDKs below 29.
    */
   @Override
   @NonNull
   public Boolean isPreviewPreTransformed() {
-    return Build.VERSION.SDK_INT <= 29;
+    return Build.VERSION.SDK_INT < 29;
   }
 }

packages/camera/camera_android_camerax/android/src/test/java/io/flutter/plugins/camerax/SystemServicesTest.java

@@ -146,16 +146,16 @@ public void isPreviewPreTransformed_returnsTrueWhenRunningBelowSdk29() {
   }
 
   @Test
-  @Config(sdk = 29)
-  public void isPreviewPreTransformed_returnsTrueWhenRunningSdk29() {
+  @Config(sdk = 28)
+  public void isPreviewPreTransformed_returnsTrueWhenRunningSdk28() {
     final SystemServicesHostApiImpl systemServicesHostApi =
         new SystemServicesHostApiImpl(mockBinaryMessenger, mockInstanceManager, mockContext);
     assertTrue(systemServicesHostApi.isPreviewPreTransformed());
   }
 
   @Test
-  @Config(sdk = 30)
-  public void isPreviewPreTransformed_returnsFalseWhenRunningAboveSdk29() {
+  @Config(sdk = 29)
+  public void isPreviewPreTransformed_returnsFalseWhenRunningAboveSdk28() {
     final SystemServicesHostApiImpl systemServicesHostApi =
         new SystemServicesHostApiImpl(mockBinaryMessenger, mockInstanceManager, mockContext);
     assertFalse(systemServicesHostApi.isPreviewPreTransformed());

packages/camera/camera_android_camerax/pubspec.yaml

@@ -2,7 +2,7 @@ name: camera_android_camerax
 description: Android implementation of the camera plugin using the CameraX library.
 repository: https://github.com/flutter/packages/tree/main/packages/camera/camera_android_camerax
 issue_tracker: https://github.com/flutter/flutter/issues?q=is%3Aissue+is%3Aopen+label%3A%22p%3A+camera%22
-version: 0.6.8+3
+version: 0.6.9
 
 environment:
   sdk: ^3.5.0