Ensure the omnibox's text isn't shorter than the cursor position

Sometimes cursorPosition computed based on mUrlBarEditingTextProvider
would be larger than the size of textWithoutAutocomplete given to
onTextChanged(). This happened when typing really fast on a slow device,
in Debug builds.

To ensure this situation doesn't trip a DCHECK within
AutocompleteControllerAndroid, use the up-to-date value of
mUrlBarEditingTextProvider's text when passing a computed cursor position.

Bug: 1142817
Change-Id: Id6ef48d561461fd711cbc9a4abab8851b8406a2a
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2503693Reviewed-by: Ted Choc <tedchoc@chromium.org>
Reviewed-by: Tomasz Wiszkowski <ender@google.com>
Commit-Queue: Ted Choc <tedchoc@chromium.org>
Auto-Submit: Maciej Pawlowski <m.pawlowski@eyeo.com>
Cr-Commit-Position: refs/heads/master@{#831920}

AUTHORS

@@ -637,6 +637,7 @@ Luke Seunghoe Gu <gulukesh@gmail.com>
 Luke Zarko <lukezarko@gmail.com>
 Luoxi Pan <l.panpax@gmail.com>
 Maarten Lankhorst <m.b.lankhorst@gmail.com>
+Maciej Pawlowski <m.pawlowski@eyeo.com>
 Magnus Danielsson <fuzzac@gmail.com>
 Mahesh Kulkarni <mahesh.kk@samsung.com>
 Mahesh Machavolu <mahesh.ma@samsung.com>

chrome/android/java/src/org/chromium/chrome/browser/omnibox/suggestions/AutocompleteMediator.java

@@ -691,38 +691,35 @@ class AutocompleteMediator implements OnSuggestionsReceivedListener, StartStopWi
             startZeroSuggest();
         } else {
             assert mRequestSuggestions == null : "Multiple omnibox requests in flight.";
-            mRequestSuggestions = () -> {
+            if (mDataProvider.hasTab() || mDataProvider.isInOverviewAndShowingOmnibox()) {
                 boolean preventAutocomplete = !mUrlBarEditingTextProvider.shouldAutocomplete();
-                mRequestSuggestions = null;
-
-                // There may be no tabs when searching form omnibox in overview mode. In that case,
-                // LocationBarDataProvider.getCurrentUrl() returns NTP url.
-                if (!mDataProvider.hasTab() && !mDataProvider.isInOverviewAndShowingOmnibox()) {
-                    // crbug.com/764749
-                    Log.w(TAG, "onTextChangedForAutocomplete: no tab");
-                    return;
-                }
-
                 Profile profile = mDataProvider.getProfile();
-                int cursorPosition = -1;
-                if (mUrlBarEditingTextProvider.getSelectionStart()
-                        == mUrlBarEditingTextProvider.getSelectionEnd()) {
-                    // Conveniently, if there is no selection, those two functions return -1,
-                    // exactly the same value needed to pass to start() to indicate no cursor
-                    // position.  Hence, there's no need to check for -1 here explicitly.
-                    cursorPosition = mUrlBarEditingTextProvider.getSelectionStart();
-                }
+                int cursorPosition = mUrlBarEditingTextProvider.getSelectionStart()
+                                == mUrlBarEditingTextProvider.getSelectionEnd()
+                        ? mUrlBarEditingTextProvider.getSelectionStart()
+                        : -1;
                 int pageClassification =
                         mDataProvider.getPageClassification(mDelegate.didFocusUrlFromFakebox());
-                mAutocomplete.start(profile, mDataProvider.getCurrentUrl(), pageClassification,
-                        textWithoutAutocomplete, cursorPosition, preventAutocomplete, null,
-                        mDelegate.didFocusUrlFromQueryTiles()
-                                || mEditSessionState == EditSessionState.ACTIVATED_BY_QUERY_TILE);
-            };
-            if (mNativeInitialized) {
-                mHandler.postDelayed(mRequestSuggestions, OMNIBOX_SUGGESTION_START_DELAY_MS);
+                String currentUrl = mDataProvider.getCurrentUrl();
+                boolean isQueryStartedFromTiles = mDelegate.didFocusUrlFromQueryTiles()
+                        || mEditSessionState == EditSessionState.ACTIVATED_BY_QUERY_TILE;
+
+                mRequestSuggestions = () -> {
+                    mRequestSuggestions = null;
+                    mAutocomplete.start(profile, currentUrl, pageClassification,
+                            textWithoutAutocomplete, cursorPosition, preventAutocomplete, null,
+                            isQueryStartedFromTiles);
+                };
+                if (mNativeInitialized) {
+                    mHandler.postDelayed(mRequestSuggestions, OMNIBOX_SUGGESTION_START_DELAY_MS);
+                } else {
+                    mDeferredNativeRunnables.add(mRequestSuggestions);
+                }
             } else {
-                mDeferredNativeRunnables.add(mRequestSuggestions);
+                // There may be no tabs when searching form omnibox in overview mode. In that case,
+                // LocationBarDataProvider.getCurrentUrl() returns NTP url.
+                // crbug.com/764749
+                Log.w(TAG, "onTextChangedForAutocomplete: no tab");
             }
         }
 

chrome/android/javatests/src/org/chromium/chrome/browser/omnibox/suggestions/AutocompleteMediatorUnitTest.java

@@ -41,6 +41,7 @@ import org.chromium.base.ContextUtils;
 import org.chromium.base.test.BaseJUnit4ClassRunner;
 import org.chromium.base.test.UiThreadTest;
 import org.chromium.base.test.util.Batch;
+import org.chromium.base.test.util.DisabledTest;
 import org.chromium.chrome.browser.flags.ChromeFeatureList;
 import org.chromium.chrome.browser.lifecycle.ActivityLifecycleDispatcher;
 import org.chromium.chrome.browser.omnibox.LocationBarDataProvider;
@@ -441,6 +442,7 @@ public class AutocompleteMediatorUnitTest {
                 .start(profile, url, pageClassification, "test", 4, false, null, false);
     }
 
+    @DisabledTest(message = "Does not test what it says: http://crbug.com/1147443")
     @Test
     @SmallTest
     @UiThreadTest