[finch testing] Add fieldtrial testing for LocationBarModelOptimizations

Bug: 905461
Change-Id: I225d2c62657688e0581fe3d3825cf1e9a5b2063c
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3668529
Commit-Queue: Peilin Wang <peilinwang@google.com>
Reviewed-by: Yaron Friedman <yfriedman@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1012588}

chrome/android/javatests/src/org/chromium/chrome/browser/toolbar/LocationBarModelTest.java

@@ -111,6 +111,8 @@ public class LocationBarModelTest {
             model.mDisplayUrl = "about:blank";
             model.mFullUrl = "about:blank";
             assertDisplayAndEditText(model, "about:blank", "about:blank");
+
+            model.destroy();
         });
     }
 

chrome/browser/ui/android/toolbar/java/src/org/chromium/chrome/browser/toolbar/LocationBarModel.java

@@ -409,18 +409,21 @@ public class LocationBarModel implements ToolbarDataProvider, LocationBarDataPro
                 autocompleteSchemeClassifier = new ChromeAutocompleteSchemeClassifier(getProfile());
             }
 
-            if (cachedSpannableDisplayText != null) {
-                return UrlBarData.forUrlAndText(url, cachedSpannableDisplayText, editingText);
-            } else {
-                OmniboxUrlEmphasizer.emphasizeUrl(spannableDisplayText,
-                        autocompleteSchemeClassifier, getSecurityLevel(), isInternalPage,
-                        shouldEmphasizeHttpsScheme(), nonEmphasizedColor, emphasizedColor,
-                        dangerColor, secureColor);
-                if (mOptimizationsEnabled) {
-                    mSpannableDisplayTextCache.put(cacheKey, spannableDisplayText);
+            try {
+                if (cachedSpannableDisplayText != null) {
+                    return UrlBarData.forUrlAndText(url, cachedSpannableDisplayText, editingText);
+                } else {
+                    OmniboxUrlEmphasizer.emphasizeUrl(spannableDisplayText,
+                            autocompleteSchemeClassifier, getSecurityLevel(), isInternalPage,
+                            shouldEmphasizeHttpsScheme(), nonEmphasizedColor, emphasizedColor,
+                            dangerColor, secureColor);
+                    if (mOptimizationsEnabled) {
+                        mSpannableDisplayTextCache.put(cacheKey, spannableDisplayText);
+                    }
                 }
+            } finally {
+                if (!mOptimizationsEnabled) autocompleteSchemeClassifier.destroy();
             }
-            if (!mOptimizationsEnabled) autocompleteSchemeClassifier.destroy();
         }
         return UrlBarData.forUrlAndText(url, spannableDisplayText, editingText);
     }

testing/variations/fieldtrial_testing_config.json

@@ -5195,6 +5195,21 @@
             ]
         }
     ],
+    "LocationBarModelOptimizations": [
+        {
+            "platforms": [
+                "android"
+            ],
+            "experiments": [
+                {
+                    "name": "Enabled",
+                    "enable_features": [
+                        "LocationBarModelOptimizations"
+                    ]
+                }
+            ]
+        }
+    ],
     "LongMessageDurationIOS": [
         {
             "platforms": [