Fix implict bp broken ui.

This CL fixes `isIconViewLoaded` logic by:
1. Check `modalities` to decide whether an icon should show.
2. If an icon should show, in `PromptIconViewBinder`, check `size` to
   update `_isIconViewLoaded` values. With this, when implicit face
   fails, size changes, `_isIconViewLoaded` could be updated to true.

Flag: N/A
Bug: 328677869
Bug: 328656309
Test: atest PromptViewModelTest
Change-Id: I04eb34ba3e2e118e4b4b9f5c8c023945880c38ff
diff --git a/packages/SystemUI/src/com/android/systemui/biometrics/ui/binder/PromptIconViewBinder.kt b/packages/SystemUI/src/com/android/systemui/biometrics/ui/binder/PromptIconViewBinder.kt
index 3469cfa..e457601 100644
--- a/packages/SystemUI/src/com/android/systemui/biometrics/ui/binder/PromptIconViewBinder.kt
+++ b/packages/SystemUI/src/com/android/systemui/biometrics/ui/binder/PromptIconViewBinder.kt
@@ -86,7 +86,12 @@
                 launch {
                     var width = 0
                     var height = 0
-                    viewModel.activeAuthType.collect { activeAuthType ->
+                    combine(promptViewModel.size, viewModel.activeAuthType, ::Pair).collect {
+                        (_, activeAuthType) ->
+                        // Every time after bp shows, [isIconViewLoaded] is set to false in
+                        // [BiometricViewSizeBinder]. Then when biometric prompt view is redrew
+                        // (when size or activeAuthType changes), we need to update
+                        // [isIconViewLoaded] here to keep it correct.
                         when (activeAuthType) {
                             AuthType.Fingerprint,
                             AuthType.Coex -> {
diff --git a/packages/SystemUI/src/com/android/systemui/biometrics/ui/viewmodel/PromptViewModel.kt b/packages/SystemUI/src/com/android/systemui/biometrics/ui/viewmodel/PromptViewModel.kt
index 61aeffe..36c7b44 100644
--- a/packages/SystemUI/src/com/android/systemui/biometrics/ui/viewmodel/PromptViewModel.kt
+++ b/packages/SystemUI/src/com/android/systemui/biometrics/ui/viewmodel/PromptViewModel.kt
@@ -217,18 +217,12 @@
      */
     val faceMode: Flow<Boolean> =
         combine(modalities, isConfirmationRequired, fingerprintStartMode) {
-                modalities: BiometricModalities,
-                isConfirmationRequired: Boolean,
-                fingerprintStartMode: FingerprintStartMode ->
-                if (modalities.hasFaceAndFingerprint) {
-                    if (isConfirmationRequired) {
-                        false
-                    } else {
-                        !fingerprintStartMode.isStarted
-                    }
-                } else {
-                    false
-                }
+                modalities,
+                isConfirmationRequired,
+                fingerprintStartMode ->
+                modalities.hasFaceAndFingerprint &&
+                    !isConfirmationRequired &&
+                    fingerprintStartMode == FingerprintStartMode.Pending
             }
             .distinctUntilChanged()
 
@@ -248,14 +242,11 @@
      * asset to be loaded before determining the prompt size.
      */
     val isIconViewLoaded: Flow<Boolean> =
-        combine(credentialKind, _isIconViewLoaded.asStateFlow()) { credentialKind, isIconViewLoaded
-            ->
-            if (credentialKind is PromptKind.Biometric) {
-                isIconViewLoaded
-            } else {
-                true
+        combine(modalities, _isIconViewLoaded.asStateFlow()) { modalities, isIconViewLoaded ->
+                val noIcon = modalities.isEmpty
+                noIcon || isIconViewLoaded
             }
-        }
+            .distinctUntilChanged()
 
     // Sets whether the prompt's iconView animation has been loaded in the view yet.
     fun setIsIconViewLoaded(iconViewLoaded: Boolean) {
diff --git a/packages/SystemUI/tests/src/com/android/systemui/biometrics/ui/viewmodel/PromptViewModelTest.kt b/packages/SystemUI/tests/src/com/android/systemui/biometrics/ui/viewmodel/PromptViewModelTest.kt
index 140849b..2f3bab4 100644
--- a/packages/SystemUI/tests/src/com/android/systemui/biometrics/ui/viewmodel/PromptViewModelTest.kt
+++ b/packages/SystemUI/tests/src/com/android/systemui/biometrics/ui/viewmodel/PromptViewModelTest.kt
@@ -1328,6 +1328,17 @@
             assertThat(logoDescription).isEqualTo(logoDescriptionFromApp)
         }
 
+    @Test
+    fun iconViewLoaded() = runGenericTest {
+        val isIconViewLoaded by collectLastValue(viewModel.isIconViewLoaded)
+        // TODO(b/328677869): Add test for noIcon logic.
+        assertThat(isIconViewLoaded).isFalse()
+
+        viewModel.setIsIconViewLoaded(true)
+
+        assertThat(isIconViewLoaded).isTrue()
+    }
+
     /** Asserts that the selected buttons are visible now. */
     private suspend fun TestScope.assertButtonsVisible(
         tryAgain: Boolean = false,