[TTS] Add new Blink tap-signals for ML.

Adds new feature signals from Blink about the page at the
location tapped.  These signals will be useful for deciding
whether to trigger Contextual Search.

Signals include the text run-length of the element tapped and
the effective font size.

BUG=754862

Change-Id: I02227479ecfae4d3b174a1845fed7c3d24e355b8
Reviewed-on: https://chromium-review.googlesource.com/920325Reviewed-by: Daniel Cheng <dcheng@chromium.org>
Commit-Queue: Donn Denman <donnd@chromium.org>
Cr-Commit-Position: refs/heads/master@{#543713}

third_party/WebKit/Source/core/exported/WebViewTest.cpp

@@ -4382,19 +4382,27 @@ class MockUnhandledTapNotifierImpl : public mojom::blink::UnhandledTapNotifier {
       mojom::blink::UnhandledTapInfoPtr unhandled_tap_info) override {
     was_unhandled_tap_ = true;
     tapped_position_ = unhandled_tap_info->tapped_position_in_viewport;
+    element_text_run_length_ = unhandled_tap_info->element_text_run_length;
+    font_size_ = unhandled_tap_info->font_size_in_pixels;
   }
   bool WasUnhandledTap() const { return was_unhandled_tap_; }
   int GetTappedXPos() const { return tapped_position_.X(); }
   int GetTappedYPos() const { return tapped_position_.Y(); }
+  int GetFontSize() const { return font_size_; }
+  int GetElementTextRunLength() const { return element_text_run_length_; }
   void Reset() {
     was_unhandled_tap_ = false;
     tapped_position_ = IntPoint();
+    element_text_run_length_ = 0;
+    font_size_ = 0;
     binding_.Close();
   }
 
  private:
   bool was_unhandled_tap_ = false;
   IntPoint tapped_position_;
+  int element_text_run_length_ = 0;
+  int font_size_ = 0;
 
   mojo::Binding<mojom::blink::UnhandledTapNotifier> binding_;
 };
@@ -4468,6 +4476,8 @@ TEST_P(ShowUnhandledTapTest, ShowUnhandledTapUIIfNeeded) {
   EXPECT_TRUE(mock_notifier_.WasUnhandledTap());
   EXPECT_EQ(64, mock_notifier_.GetTappedXPos());
   EXPECT_EQ(278, mock_notifier_.GetTappedYPos());
+  EXPECT_EQ(16, mock_notifier_.GetFontSize());
+  EXPECT_EQ(7, mock_notifier_.GetElementTextRunLength());
 
   // Test basic tap handling and notification.
   Tap("target");
@@ -4483,6 +4493,8 @@ TEST_P(ShowUnhandledTapTest, ShowUnhandledTapUIIfNeeded) {
   EXPECT_TRUE(mock_notifier_.WasUnhandledTap());
   EXPECT_EQ(188, mock_notifier_.GetTappedXPos());
   EXPECT_EQ(124, mock_notifier_.GetTappedYPos());
+  EXPECT_EQ(16, mock_notifier_.GetFontSize());
+  EXPECT_EQ(28, mock_notifier_.GetElementTextRunLength());
 }
 
 TEST_P(ShowUnhandledTapTest, ShowUnhandledTapUIIfNeededWithMutateDom) {
@@ -4514,7 +4526,7 @@ TEST_P(ShowUnhandledTapTest, ShowUnhandledTapUIIfNeededWithPreventDefault) {
 }
 
 TEST_P(ShowUnhandledTapTest, ShowUnhandledTapUIIfNeededWithNonTriggeringNodes) {
-  Tap("checkbox");
+  Tap("image");
   EXPECT_FALSE(mock_notifier_.WasUnhandledTap());
 
   Tap("editable");
@@ -4524,6 +4536,16 @@ TEST_P(ShowUnhandledTapTest, ShowUnhandledTapUIIfNeededWithNonTriggeringNodes) {
   EXPECT_FALSE(mock_notifier_.WasUnhandledTap());
 }
 
+TEST_P(ShowUnhandledTapTest, ShowUnhandledTapUIIfNeededWithTextSizes) {
+  Tap("large");
+  EXPECT_TRUE(mock_notifier_.WasUnhandledTap());
+  EXPECT_EQ(20, mock_notifier_.GetFontSize());
+
+  Tap("small");
+  EXPECT_TRUE(mock_notifier_.WasUnhandledTap());
+  EXPECT_EQ(10, mock_notifier_.GetFontSize());
+}
+
 #endif  // BUILDFLAG(ENABLE_UNHANDLED_TAP)
 
 TEST_P(WebViewTest, StopLoadingIfJavaScriptURLReturnsNoStringResult) {

third_party/WebKit/Source/core/input/GestureManager.cpp

@@ -21,7 +21,11 @@
 #include "public/public_features.h"
 
 #if BUILDFLAG(ENABLE_UNHANDLED_TAP)
+#include "core/editing/FrameSelection.h"
+#include "core/editing/SelectionTemplate.h"
+#include "core/editing/VisibleSelection.h"
 #include "core/frame/LocalFrameClient.h"
+#include "core/style/ComputedStyle.h"
 #include "public/platform/unhandled_tap_notifier.mojom-blink.h"
 #include "public/web/WebNode.h"
 #include "services/service_manager/public/cpp/interface_provider.h"
@@ -310,7 +314,7 @@ WebInputEventResult GestureManager::HandleGestureTap(
         frame_->GetPage()->GetVisualViewport().RootFrameToViewport(
             tapped_position);
     ShowUnhandledTapUIIfNeeded(dom_tree_changed, style_changed, tapped_node,
-                               tapped_position_in_viewport);
+                               tapped_element, tapped_position_in_viewport);
   }
   return event_result;
 }
@@ -447,9 +451,11 @@ void GestureManager::ShowUnhandledTapUIIfNeeded(
     bool dom_tree_changed,
     bool style_changed,
     Node* tapped_node,
+    Element* tapped_element,
     const IntPoint& tapped_position_in_viewport) {
 #if BUILDFLAG(ENABLE_UNHANDLED_TAP)
   WebNode web_node(tapped_node);
+  // TODO(donnd): roll in ML-identified signals for suppression once identified.
   bool should_trigger = !dom_tree_changed && !style_changed &&
                         tapped_node->IsTextNode() &&
                         !web_node.IsContentEditable() &&
@@ -457,12 +463,29 @@ void GestureManager::ShowUnhandledTapUIIfNeeded(
   // Renderer-side trigger-filtering to minimize messaging.
   // The Browser may do additional trigger-filtering.
   if (should_trigger) {
-    WebPoint point(tapped_position_in_viewport.X(),
-                   tapped_position_in_viewport.Y());
-    auto tapped_info = mojom::blink::UnhandledTapInfo::New(point);
+    // Start setting up the Mojo interface connection.
     mojom::blink::UnhandledTapNotifierPtr provider;
     frame_->Client()->GetInterfaceProvider()->GetInterface(
         mojo::MakeRequest(&provider));
+
+    // Extract text run-length.
+    int text_run_length = 0;
+    if (tapped_element)
+      text_run_length = tapped_element->textContent().length();
+
+    // Compute the style of the tapped node to extract text characteristics.
+    const ComputedStyle* style = tapped_node->EnsureComputedStyle();
+    int font_size = 0;
+    if (style)
+      font_size = style->FontSize();
+    // TODO(donnd): get the text color and style and return,
+    // e.g. style->GetFontWeight() to return bold.  Need italic, color, etc.
+
+    // Notify the Browser.
+    WebPoint point(tapped_position_in_viewport.X(),
+                   tapped_position_in_viewport.Y());
+    auto tapped_info =
+        mojom::blink::UnhandledTapInfo::New(point, font_size, text_run_length);
     provider->ShowUnhandledTapUIIfNeeded(std::move(tapped_info));
   }
 #endif  // BUILDFLAG(ENABLE_UNHANDLED_TAP)

third_party/WebKit/Source/core/input/GestureManager.h

@@ -64,6 +64,7 @@ class CORE_EXPORT GestureManager
   void ShowUnhandledTapUIIfNeeded(bool dom_tree_changed,
                                   bool style_changed,
                                   Node* tapped_node,
+                                  Element* tapped_element,
                                   const IntPoint& tapped_position_in_viewport);
 
   // NOTE: If adding a new field to this class please ensure that it is

third_party/WebKit/Source/core/testing/data/show_unhandled_tap.html

@@ -16,16 +16,25 @@
 :indeterminate + span {
   background-color: blue;
 }
+#large {
+  font-size: 20px;
+}
+#small {
+  font-size: 10px;
+}
 </style>
 </head>
 <body>
-<div style="position: absolute; left: 8px; top: 66px; width: 400px; height: 30px;">
+<div style="position: absolute; left: 8px; top: 66px; width: 400px; height: 350px;">
 <span id="target">This has multiple listeners.</span>
 <div id="mutate">This block gets mutated to change the DOM.</div>
 <div id="style_active">This block gets red if active</div>
-<input id="checkbox" type="checkbox"><span>indeterminate checkbox</span>
-<input id="editable" type="text" value="editable">
-<div id="focusable" tabindex="1">focusable</div>
+<input id="checkbox" type="checkbox"><span>indeterminate checkbox</span><br>
+<img id="image" width="10" height="10" src="data:image/gif;base64,R0lGODlhAQABAIAAAAUEBAAAACwAAAAAAQABAAACAkQBADs="><br>
+<span id="editable" contenteditable="true">editable</span><br>
+<span id="focusable" tabindex="1">focusable</span><br>
+<span id="large">large</span><br>
+<span id="small">small</span><br>
 </div>
 
 <p style="position: absolute; left: 8px; top: 400px; width: 400px; height: 30px;"><span id="bottom">Bottom.</span></p>
@@ -33,14 +42,17 @@
 <script>
 var test;
 var mutations = 0;
+// Remembers which test to run.
 function setTest(whichTest) {
   test = whichTest;
 }
+// Determines if we currently have a test for the given event/handler pair.
 function hasTest(operation, handler) {
   var candidate = operation + '-' + handler;
   var result = test === candidate;
   return result;
 }
+// Our universal event handler.  Changes the page based on the stored operation.
 function handle(event) {
   var operation = event.type;
   if (hasTest(operation, 'mutateDom')) {
@@ -54,6 +66,7 @@ function handle(event) {
     event.preventDefault();
   }
 }
+// Set up $target to have the handle() handler for all tap-related events.
 var t = document.getElementById('target');
 t.addEventListener('mousedown', handle);
 t.addEventListener('mouseup', handle);

third_party/WebKit/public/platform/unhandled_tap_notifier.mojom

@@ -11,6 +11,9 @@ import "ui/gfx/geometry/mojo/geometry.mojom";
 // This data is used to notifying the Browser to show UI for an unhandled tap if needed.
 struct UnhandledTapInfo {
     gfx.mojom.Point tapped_position_in_viewport;
+    // These values default to 0,  which indicates an undetermined value.
+    uint32 font_size_in_pixels = 0;
+    uint32 element_text_run_length = 0;
 };
 
 interface UnhandledTapNotifier {