blink: Enable the GPU trigger when viewport meta tag is not read

Source/web/WebSettingsImpl.h

Index: Source/web/WebSettingsImpl.h
diff --git a/Source/web/WebSettingsImpl.h b/Source/web/WebSettingsImpl.h
index ce8b35c84f787625e79cef8fcb4c21221683cf39..a54f03d1b5ab1736e88a7ed2b7aa284b85bbf217 100644
--- a/Source/web/WebSettingsImpl.h
+++ b/Source/web/WebSettingsImpl.h
@@ -188,6 +188,7 @@ public:
     bool doubleTapToZoomEnabled() const { return m_doubleTapToZoomEnabled; }
     bool perTilePaintingEnabled() const { return m_perTilePaintingEnabled; }
     bool supportDeprecatedTargetDensityDPI() const { return m_supportDeprecatedTargetDensityDPI; }
+    bool viewportMetaEnabled() const;
     bool viewportMetaLayoutSizeQuirk() const { return m_viewportMetaLayoutSizeQuirk; }
     bool viewportMetaNonUserScalableQuirk() const { return m_viewportMetaNonUserScalableQuirk; }
     bool clobberUserAgentInitialScaleQuirk() const { return m_clobberUserAgentInitialScaleQuirk; }