Expand WTF::StringView's API to be more like StringPiece.

third_party/WebKit/Source/core/paint/InlineTextBoxPainter.cpp

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "core/paint/InlineTextBoxPainter.h"
 
 #include "core/editing/CompositionUnderline.h"
 #include "core/editing/Editor.h"
 #include "core/editing/markers/DocumentMarkerController.h"
 #include "core/editing/markers/RenderedDocumentMarker.h"
@@ skipping 131 matching lines @@
         if (haveSelection && !paintsCompositionMarkers(textBoxLayoutObject)) {
             if (combinedText)
                 paintSelection<InlineTextBoxPainter::PaintOptions::CombinedText>(context, boxRect, styleToUse, font, selectionStyle.fillColor, combinedText);
             else
                 paintSelection<InlineTextBoxPainter::PaintOptions::Normal>(context, boxRect, styleToUse, font, selectionStyle.fillColor);
         }
     }
 
     // 2. Now paint the foreground, including text and decorations like underline/overline (in quirks mode only).
     int length = m_inlineTextBox.len();
-    StringView string = m_inlineTextBox.getLineLayoutItem().text().createView();
-    ASSERT(m_inlineTextBox.start() + length <= string.length());
-    if (static_cast<unsigned>(length) != string.length() || m_inlineTextBox.start())
-        string.narrow(m_inlineTextBox.start(), length);
+    StringView string = StringView(m_inlineTextBox.getLineLayoutItem().text(), m_inlineTextBox.start(), length);
     int maximumLength = m_inlineTextBox.getLineLayoutItem().textLength() - m_inlineTextBox.start();
 
     StringBuilder charactersWithHyphen;
     TextRun textRun = m_inlineTextBox.constructTextRun(styleToUse, font, string, maximumLength, m_inlineTextBox.hasHyphen() ? &charactersWithHyphen : 0);
     if (m_inlineTextBox.hasHyphen())
         length = textRun.length();
 
     int selectionStart = 0;
     int selectionEnd = 0;
     if (paintSelectedTextOnly || paintSelectedTextSeparately)
@@ skipping 268 matching lines @@
         return;
 
     // If the text color ends up being the same as the selection background, invert the selection
     // background.
     if (textColor == c)
         c = Color(0xff - c.red(), 0xff - c.green(), 0xff - c.blue());
 
     // If the text is truncated, let the thing being painted in the truncation
     // draw its own highlight.
     int length = m_inlineTextBox.truncation() != cNoTruncation ? m_inlineTextBox.truncation() : m_inlineTextBox.len();
-    StringView string = m_inlineTextBox.getLineLayoutItem().text().createView();
-
-    if (string.length() != static_cast<unsigned>(length) || m_inlineTextBox.start())
-        string.narrow(m_inlineTextBox.start(), length);
+    StringView string(m_inlineTextBox.getLineLayoutItem().text(), m_inlineTextBox.start(), static_cast<unsigned>(length));
 
     StringBuilder charactersWithHyphen;
     bool respectHyphen = ePos == length && m_inlineTextBox.hasHyphen();
     TextRun textRun = m_inlineTextBox.constructTextRun(style, font, string, m_inlineTextBox.getLineLayoutItem().textLength() - m_inlineTextBox.start(), respectHyphen ? &charactersWithHyphen : 0);
     if (respectHyphen)
         ePos = textRun.length();
 
     GraphicsContextStateSaver stateSaver(context);
 
     if (options == InlineTextBoxPainter::PaintOptions::CombinedText) {
@@ skipping 395 matching lines @@
 
     Color color = LayoutTheme::theme().platformTextSearchHighlightColor(marker->activeMatch());
     GraphicsContext& context = paintInfo.context;
     GraphicsContextStateSaver stateSaver(context);
     context.clip(FloatRect(boxOrigin.x().toFloat(), (boxOrigin.y() - deltaY).toFloat(), m_inlineTextBox.logicalWidth().toFloat(), selHeight));
     context.drawHighlightForText(font, run, FloatPoint(boxOrigin.x().toFloat(), (boxOrigin.y() - deltaY).toFloat()), selHeight, color, sPos, ePos);
 }
 
 
 } // namespace blink