Avoid multiple calls to onPageFinished (#4247)

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Task/Issue URL:
https://app.asana.com/0/488551667048375/1206636072031849/f

### Description
This PR prevents logic inside onPageFinished to be executed unless
progress is 100.

### Steps to test this PR
Smoke tests

app/src/androidTest/java/com/duckduckgo/app/browser/BrowserWebViewClientTest.kt

@@ -789,6 +789,64 @@ class BrowserWebViewClientTest {
         assertEquals(10L, endArgumentCaptor.firstValue)
     }
 
+    @UiThreadTest
+    @Test
+    fun whenOnPageFinishedCalledBeforeCompletionThenJsCodeNotInjected() {
+        val mockWebView = getImmediatelyInvokedMockWebView()
+        whenever(mockWebView.progress).thenReturn(10)
+        whenever(mockWebView.settings).thenReturn(mock())
+
+        assertEquals(0, jsPlugins.plugin.countFinished)
+        testee.onPageFinished(mockWebView, EXAMPLE_URL)
+        assertEquals(0, jsPlugins.plugin.countFinished)
+        assertEquals(0, jsPlugins.plugin.countStarted)
+    }
+
+    @Test
+    fun whenOnPageFinishedCalledBeforeCompleteThenVerifyVerificationCompletedNotCalled() {
+        val mockWebView = getImmediatelyInvokedMockWebView()
+        whenever(mockWebView.progress).thenReturn(10)
+        whenever(mockWebView.settings).thenReturn(mock())
+        whenever(mockWebView.safeCopyBackForwardList()).thenReturn(TestBackForwardList())
+
+        testee.onPageFinished(mockWebView, EXAMPLE_URL)
+        verifyNoInteractions(internalTestUserChecker)
+    }
+
+    @UiThreadTest
+    @Test
+    fun whenOnPageFinishedCalledBeforeCompleteThenNavigationStateNotInvoked() {
+        val mockWebView = getImmediatelyInvokedMockWebView()
+        whenever(mockWebView.progress).thenReturn(10)
+        whenever(mockWebView.settings).thenReturn(mock())
+        whenever(mockWebView.safeCopyBackForwardList()).thenReturn(TestBackForwardList())
+
+        testee.onPageFinished(mockWebView, EXAMPLE_URL)
+        verifyNoInteractions(listener)
+    }
+
+    @Test
+    fun whenOnPageFinishedCalledThenPrintInjectorInjected() {
+        val mockWebView = getImmediatelyInvokedMockWebView()
+        whenever(mockWebView.progress).thenReturn(100)
+        whenever(mockWebView.settings).thenReturn(mock())
+        whenever(mockWebView.safeCopyBackForwardList()).thenReturn(TestBackForwardList())
+
+        testee.onPageFinished(mockWebView, EXAMPLE_URL)
+        verify(printInjector).injectPrint(mockWebView)
+    }
+
+    @Test
+    fun whenOnPageFinishedBeforeCompleteThenPrintInjectorNotInjected() {
+        val mockWebView = getImmediatelyInvokedMockWebView()
+        whenever(mockWebView.progress).thenReturn(10)
+        whenever(mockWebView.settings).thenReturn(mock())
+        whenever(mockWebView.safeCopyBackForwardList()).thenReturn(TestBackForwardList())
+
+        testee.onPageFinished(mockWebView, EXAMPLE_URL)
+        verifyNoInteractions(printInjector)
+    }
+
     private class TestWebView(context: Context) : WebView(context) {
         override fun getOriginalUrl(): String {
             return EXAMPLE_URL

app/src/main/java/com/duckduckgo/app/browser/BrowserWebViewClient.kt

@@ -302,29 +302,31 @@ class BrowserWebViewClient @Inject constructor(
         webView: WebView,
         url: String?,
     ) {
-        jsPlugins.getPlugins().forEach {
-            it.onPageFinished(webView, url, webViewClientListener?.getSite())
-        }
-        url?.let {
-            // We call this for any url but it will only be processed for an internal tester verification url
-            internalTestUserChecker.verifyVerificationCompleted(it)
-        }
-        Timber.v("onPageFinished webViewUrl: ${webView.url} URL: $url")
-        val navigationList = webView.safeCopyBackForwardList() ?: return
-        webViewClientListener?.run {
-            navigationStateChanged(WebViewNavigationState(navigationList))
-            url?.let { prefetchFavicon(url) }
-        }
-        flushCookies()
-        printInjector.injectPrint(webView)
-
-        url?.let {
-            start?.let { safeStart ->
-                val progress = webView.progress
-                // See https://app.asana.com/0/0/1206159443951489/f (WebView limitations)
-                if (url != ABOUT_BLANK && progress == 100) {
-                    shouldSendPageLoadedPixel(it, safeStart, currentTimeProvider.getTimeInMillis())
-                    start = null
+        Timber.v("onPageFinished webViewUrl: ${webView.url} URL: $url progress: ${webView.progress}")
+        if (webView.progress == 100) {
+            jsPlugins.getPlugins().forEach {
+                it.onPageFinished(webView, url, webViewClientListener?.getSite())
+            }
+            url?.let {
+                // We call this for any url but it will only be processed for an internal tester verification url
+                internalTestUserChecker.verifyVerificationCompleted(it)
+            }
+            val navigationList = webView.safeCopyBackForwardList() ?: return
+            webViewClientListener?.run {
+                navigationStateChanged(WebViewNavigationState(navigationList))
+                url?.let { prefetchFavicon(url) }
+            }
+            flushCookies()
+            printInjector.injectPrint(webView)
+
+            url?.let {
+                start?.let { safeStart ->
+                    val progress = webView.progress
+                    // See https://app.asana.com/0/0/1206159443951489/f (WebView limitations)
+                    if (url != ABOUT_BLANK) {
+                        shouldSendPageLoadedPixel(it, safeStart, currentTimeProvider.getTimeInMillis())
+                        start = null
+                    }
                 }
             }
         }