Reland: Move DIP scale away from AwContents

This small refactoring removes device scale factor from AwContents
cache and uses the value from ContentViewCore.
The device scale factor in ContentViewCore is defined after
ContentViewCore native initialization, therefore this CL also
moves the device scale propagation until after that.

This is a prerequisite for https://codereview.chromium.org/2300463002

BUG=620929

> Committed: https://crrev.com/8d849fd2d39c9db747f4e8d89dcedfebb0273a97
> Cr-Commit-Position: refs/heads/master@{#415546}

Reland after fix related to PopupTouchHandleDrawable.

Review-Url: https://codereview.chromium.org/2288273003
Cr-Commit-Position: refs/heads/master@{#415690}

android_webview/java/src/org/chromium/android_webview/AwContents.java

@@ -75,7 +75,6 @@ import org.chromium.ui.base.ActivityWindowAndroid;
 import org.chromium.ui.base.PageTransition;
 import org.chromium.ui.base.ViewAndroidDelegate;
 import org.chromium.ui.base.WindowAndroid;
-import org.chromium.ui.gfx.DeviceDisplayInfo;
 
 import java.io.File;
 import java.lang.annotation.Annotation;
@@ -302,8 +301,6 @@ public class AwContents implements SmartClipProvider,
 
     private Bitmap mFavicon;
     private boolean mHasRequestedVisitedHistoryFromClient;
-    // TODO(boliu): This should be in a global context, not per webview.
-    private final double mDIPScale;
     // Whether this WebView is a popup.
     private boolean mIsPopupWindow = false;
 
@@ -772,9 +769,7 @@ public class AwContents implements SmartClipProvider,
         mContentViewClient = new AwContentViewClient(contentsClient, settings, this, mContext);
         mLayoutSizer = dependencyFactory.createLayoutSizer();
         mSettings = settings;
-        mDIPScale = DeviceDisplayInfo.create(mContext).getDIPScale();
         mLayoutSizer.setDelegate(new AwLayoutSizerDelegate());
-        mLayoutSizer.setDIPScale(mDIPScale);
         mWebContentsDelegate = new AwWebContentsDelegateAdapter(
                 this, contentsClient, mContentViewClient, mContext, mContainerView);
         mContentsClientBridge = new AwContentsClientBridge(mContext, contentsClient,
@@ -805,7 +800,6 @@ public class AwContents implements SmartClipProvider,
         mDefaultVideoPosterRequestHandler = new DefaultVideoPosterRequestHandler(mContentsClient);
         mSettings.setDefaultVideoPosterURL(
                 mDefaultVideoPosterRequestHandler.getDefaultVideoPosterURL());
-        mSettings.setDIPScale(mDIPScale);
         mScrollOffsetManager =
                 dependencyFactory.createScrollOffsetManager(new AwScrollOffsetManagerDelegate());
         mScrollAccessibilityHelper = new ScrollAccessibilityHelper(mContainerView);
@@ -1066,7 +1060,12 @@ public class AwContents implements SmartClipProvider,
         mNavigationController = mWebContents.getNavigationController();
         installWebContentsObserver();
         mSettings.setWebContents(webContents);
-        nativeSetDipScale(mNativeAwContents, (float) mDIPScale);
+
+        float dipScale = mContentViewCore.getDeviceScaleFactor();
+        nativeSetDipScale(mNativeAwContents, dipScale);
+        mLayoutSizer.setDIPScale(dipScale);
+        mSettings.setDIPScale(dipScale);
+
         updateContentViewCoreVisibility();
 
         // The native side object has been bound to this java instance, so now is the time to
@@ -2101,7 +2100,7 @@ public class AwContents implements SmartClipProvider,
      */
     public float getScale() {
         if (isDestroyed(WARN)) return 1;
-        return (float) (mPageScaleFactor * mDIPScale);
+        return (float) (mPageScaleFactor * mContentViewCore.getDeviceScaleFactor());
     }
 
     /**
@@ -2684,8 +2683,8 @@ public class AwContents implements SmartClipProvider,
 
     @CalledByNative
     private long onCreateTouchHandle() {
-        PopupTouchHandleDrawable drawable =
-                PopupTouchHandleDrawable.create(mTouchHandleDrawables, mContentViewCore, mDIPScale);
+        PopupTouchHandleDrawable drawable = PopupTouchHandleDrawable.create(
+                mTouchHandleDrawables, mContentViewCore, mContentViewCore.getDeviceScaleFactor());
         return drawable.getNativeDrawable();
     }
 
@@ -2879,9 +2878,9 @@ public class AwContents implements SmartClipProvider,
         if (mPageScaleFactor != pageScaleFactor) {
             float oldPageScaleFactor = mPageScaleFactor;
             mPageScaleFactor = pageScaleFactor;
+            float dipScale = mContentViewCore.getDeviceScaleFactor();
             mContentsClient.getCallbackHelper().postOnScaleChangedScaled(
-                    (float) (oldPageScaleFactor * mDIPScale),
-                    (float) (mPageScaleFactor * mDIPScale));
+                    oldPageScaleFactor * dipScale, mPageScaleFactor * dipScale);
         }
     }
 
@@ -3107,10 +3106,10 @@ public class AwContents implements SmartClipProvider,
             if (event.getActionMasked() == MotionEvent.ACTION_DOWN) {
                 // Note this will trigger IPC back to browser even if nothing is
                 // hit.
+                float dipScale = mContentViewCore.getDeviceScaleFactor();
                 nativeRequestNewHitTestDataAt(mNativeAwContents,
-                        event.getX() / (float) mDIPScale,
-                        event.getY() / (float) mDIPScale,
-                        Math.max(event.getTouchMajor(), event.getTouchMinor()) / (float) mDIPScale);
+                        event.getX() / dipScale, event.getY() / dipScale,
+                        Math.max(event.getTouchMajor(), event.getTouchMinor()) / dipScale);
             }
 
             if (mOverScrollGlow != null) {