[Smart Text] Disable surrounding text for input elements.

This CL effectively reverts
https://codereview.chromium.org/2907963002, which appears to
causing problems, including leaking of input fields to
Google servers.

Disabling until a better fix is found.

BUG=751408, 753579, 721840

Change-Id: Iecddba6ebed8faf3c266daa232613c57fa5a7464
Reviewed-on: https://chromium-review.googlesource.com/622747Reviewed-by: Yoshifumi Inoue <yosin@chromium.org>
Commit-Queue: Tima Vaisburd <timav@chromium.org>
Cr-Commit-Position: refs/heads/master@{#495985}

third_party/WebKit/Source/core/editing/SurroundingText.cpp

@@ -64,14 +64,11 @@ void SurroundingText::Initialize(const Position& start_position,
     return;
   DCHECK(!document->NeedsLayoutTreeUpdate());
 
-  // The forward range starts at the selection end and ends at the document's
-  // or the input element's end. It will then be updated to only contain the
-  // text in the right range around the selection.
+  // Do not create surrounding text for input elements.
   DCHECK_EQ(RootEditableElementOf(start_position),
             RootEditableElementOf(end_position));
-  Element* const root_editable = RootEditableElementOf(start_position);
-  Element* const root_element =
-      root_editable ? root_editable : document->documentElement();
+  if (RootEditableElementOf(start_position))
+    return;
 
   // Do not create surrounding text if start or end position is within a
   // control.
@@ -81,9 +78,13 @@ void SurroundingText::Initialize(const Position& start_position,
           end_position.ComputeContainerNode()))
     return;
 
+  // The forward range starts at the selection end and ends at the document's
+  // end. It will then be updated to only contain the text in the right range
+  // around the selection.
   CharacterIterator forward_iterator(
       end_position,
-      Position::LastPositionInNode(*root_element).ParentAnchoredEquivalent(),
+      Position::LastPositionInNode(*document->documentElement())
+          .ParentAnchoredEquivalent(),
       TextIteratorBehavior::Builder().SetStopsOnFormControls(true).Build());
   if (!forward_iterator.AtEnd())
     forward_iterator.Advance(max_length - half_max_length);
@@ -92,7 +93,8 @@ void SurroundingText::Initialize(const Position& start_position,
   // starts at the document's or input element's start and ends at the selection
   // start and will be updated.
   BackwardsCharacterIterator backwards_iterator(
-      Position::FirstPositionInNode(*root_element).ParentAnchoredEquivalent(),
+      Position::FirstPositionInNode(*document->documentElement())
+          .ParentAnchoredEquivalent(),
       start_position,
       TextIteratorBehavior::Builder().SetStopsOnFormControls(true).Build());
   if (!backwards_iterator.AtEnd())

third_party/WebKit/Source/core/editing/SurroundingTextTest.cpp

@@ -11,7 +11,6 @@
 #include "core/editing/Position.h"
 #include "core/editing/VisibleSelection.h"
 #include "core/html/HTMLElement.h"
-#include "core/html/TextControlElement.h"
 #include "core/testing/DummyPageHolder.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
@@ -286,24 +285,4 @@ TEST_F(SurroundingTextTest, TreeRangeSelection) {
   }
 }
 
-TEST_F(SurroundingTextTest, TextAreaSelection) {
-  SetHTML(
-      String("<p>First paragraph</p>"
-             "<textarea id='selection'>abc def ghi</textarea>"
-             "<p>Second paragraph</p>"));
-
-  TextControlElement* text_ctrl =
-      (TextControlElement*)GetDocument().getElementById("selection");
-
-  text_ctrl->SetSelectionRange(4, 7);
-  VisibleSelection selection = CreateVisibleSelection(text_ctrl->Selection());
-
-  SurroundingText surrounding_text(
-      *CreateRange(FirstEphemeralRangeOf(selection)), 20);
-
-  EXPECT_EQ("abc def ghi", surrounding_text.Content().SimplifyWhiteSpace());
-  EXPECT_EQ(4u, surrounding_text.StartOffsetInContent());
-  EXPECT_EQ(7u, surrounding_text.EndOffsetInContent());
-}
-
 }  // namespace blink