Add "Paste as plain text" into text selection toolbar overflow

content/public/android/java/src/org/chromium/content/browser/SelectionPopupController.java

Index: content/public/android/java/src/org/chromium/content/browser/SelectionPopupController.java
diff --git a/content/public/android/java/src/org/chromium/content/browser/SelectionPopupController.java b/content/public/android/java/src/org/chromium/content/browser/SelectionPopupController.java
index df436286db9f02491051f09dbb0e97f44afb2607..e840629f8e3fd511287e0ca62d1c6fc10b889e80 100644
--- a/content/public/android/java/src/org/chromium/content/browser/SelectionPopupController.java
+++ b/content/public/android/java/src/org/chromium/content/browser/SelectionPopupController.java
@@ -7,6 +7,8 @@ package org.chromium.content.browser;
 import android.annotation.TargetApi;
 import android.app.Activity;
 import android.app.SearchManager;
+import android.content.ClipData;
+import android.content.ClipDescription;
 import android.content.ClipboardManager;
 import android.content.Context;
 import android.content.Intent;
@@ -16,7 +18,11 @@ import android.content.res.Resources;
 import android.graphics.Rect;
 import android.os.Build;
 import android.provider.Browser;
+import android.text.Spanned;
 import android.text.TextUtils;
+import android.text.style.CharacterStyle;
+import android.text.style.ParagraphStyle;
+import android.text.style.UpdateAppearance;
 import android.view.ActionMode;
 import android.view.Menu;
 import android.view.MenuInflater;
@@ -107,6 +113,7 @@ public class SelectionPopupController extends ActionModeCallbackHelper {
     private boolean mIsPasswordType;
     private boolean mIsInsertion;
     private boolean mCanSelectAllForPastePopup;
+    private boolean mCanEditRichlyForPastePopup;
 
     private boolean mUnselectAllOnDismiss;
     private String mLastSelectedText;
@@ -261,7 +268,7 @@ public class SelectionPopupController extends ActionModeCallbackHelper {
         return actionMode;
     }
 
-    void createAndShowPastePopup(int x, int y, boolean canSelectAll) {
+    void createAndShowPastePopup(int x, int y, boolean canSelectAll, boolean canEditRichly) {
         if (mView.getParent() == null || mView.getVisibility() != View.VISIBLE) {
             return;
         }
@@ -269,6 +276,7 @@ public class SelectionPopupController extends ActionModeCallbackHelper {
         if (!supportsFloatingActionMode() && !canPaste()) return;
         destroyPastePopup();
         mCanSelectAllForPastePopup = canSelectAll;
+        mCanEditRichlyForPastePopup = canEditRichly;
         PastePopupMenuDelegate delegate = new PastePopupMenuDelegate() {
             @Override
             public void paste() {
@@ -277,6 +285,12 @@ public class SelectionPopupController extends ActionModeCallbackHelper {
             }
 
             @Override
+            public void pasteAsPlainText() {
+                mWebContents.pasteAsPlainText();
+                mWebContents.dismissTextHandles();
+            }
+
+            @Override
             public boolean canPaste() {
                 return SelectionPopupController.this.canPaste();
             }
@@ -290,6 +304,11 @@ public class SelectionPopupController extends ActionModeCallbackHelper {
             public boolean canSelectAll() {
                 return SelectionPopupController.this.canSelectAll();
             }
+
+            @Override
+            public boolean canPasteAsPlainText() {
+                return SelectionPopupController.this.canPasteAsPlainText();
+            }
         };
         Context windowContext = mWindowAndroid.getContext().get();
         if (windowContext == null) return;
@@ -509,6 +528,39 @@ public class SelectionPopupController extends ActionModeCallbackHelper {
         return clipMgr.hasPrimaryClip();
     }
 
+    // Only check those classes affect appearance.
+    private boolean hasStyleSpan(Spanned spanned) {
+        Class<?>[] styleClasses = {
+                CharacterStyle.class, ParagraphStyle.class, UpdateAppearance.class};
+        for (Class<?> clazz : styleClasses) {
+            if (spanned.nextSpanTransition(-1, spanned.length(), clazz) < spanned.length()) {
+                return true;
+            }
+        }
+        return false;
+    }
+
+    // if need to show paste as plain text.
+    @VisibleForTesting
+    public boolean canPasteAsPlainText() {
+        if (!BuildInfo.isAtLeastO()) return false;

[boliu, 2017/05/02 17:31:57]

comment explaining why this is O only

[Shimi Zhang, 2017/05/03 00:37:17]

Done.

+        if (!mCanEditRichlyForPastePopup) return false;
+        ClipboardManager clipMgr =
+                (ClipboardManager) mContext.getSystemService(Context.CLIPBOARD_SERVICE);
+        if (!clipMgr.hasPrimaryClip()) return false;
+
+        // In case that plain text is a Spanned.
+        ClipData clipData = clipMgr.getPrimaryClip();
+        ClipDescription description = clipData.getDescription();
+        CharSequence text = clipData.getItemAt(0).getText();
+        boolean isPlainType = description.hasMimeType(ClipDescription.MIMETYPE_TEXT_PLAIN);
+        if (isPlainType && (text instanceof Spanned)) {
+            Spanned spanned = (Spanned) text;
+            if (hasStyleSpan(spanned)) return true;

[boliu, 2017/05/02 17:31:57]

can you explain this check? android APIs docs are quite bare and I dunno what
these style classes really mean

[Shimi Zhang, 2017/05/03 00:37:17]

Per a discussion with TextView developer, those three classes will affect text
appearance, Android APIs has more such classes, but used for other purpose. So
we check only those spans viewable to users.

[boliu, 2017/05/03 00:44:44]

This basically needs a comment explaining to some random chromium developer
passing by why this code is here and correct. And "discussion with textview
developer" is pretty meaningless here.

And I still don't understand what this hasStyleSpan method is doing.

+        }
+        return description.hasMimeType(ClipDescription.MIMETYPE_TEXT_HTML);
+    }
+
     private void updateAssistMenuItem(MenuDescriptor descriptor) {
         // There is no Assist functionality before Android O.
         if (!BuildInfo.isAtLeastO() || mAssistMenuItemId == 0) return;
@@ -696,6 +748,14 @@ public class SelectionPopupController extends ActionModeCallbackHelper {
     }
 
     /**
+     * Perform a paste as plain text action.
+     */
+    @VisibleForTesting
+    void pasteAsPlainText() {
+        mWebContents.pasteAsPlainText();
+    }
+
+    /**
      * Perform a share action.
      */
     @VisibleForTesting