Fix setInitialScale() to take display density into account.

Reverted changes made to fix bug 4982074 (Book text display is limited
to about half the available screen.) The Books app sets initial scale to
100%, and since display density for Crespo is 1.5, initial scale was
actually being set to a smaller value in Device Independent Pixel units.

The correct fix is to take display density into account. This fixes bug
5477652: webview scale factor wrong on prime in reddit app.

Change-Id: Ie09172629add7fb28ca6b47d0fd8f6450c5df569

Author: mghiware

core/java/android/webkit/ZoomManager.java

@@ -169,11 +169,7 @@ class ZoomManager {
 
     /*
      * The initial scale for the WebView. 0 means default. If initial scale is
-     * greater than 0 the WebView starts with this value as its initial scale. The
-     * value is converted from an integer percentage so it is guarenteed to have
-     * no more than 2 significant digits after the decimal.  This restriction
-     * allows us to convert the scale back to the original percentage by simply
-     * multiplying the value by 100.
+     * greater than 0, the WebView starts with this value as its initial scale.
      */
     private float mInitialScale;
 
@@ -313,7 +309,7 @@ public final float getMinZoomScale() {
     }
 
     public final float getDefaultScale() {
-        return mInitialScale > 0 ? mInitialScale : mDefaultScale;
+        return mDefaultScale;
     }
 
     /**
@@ -353,9 +349,7 @@ public final void setZoomCenter(float x, float y) {
     }
 
     public final void setInitialScaleInPercent(int scaleInPercent) {
-        mInitialScale = scaleInPercent * 0.01f;
-        mActualScale = mInitialScale > 0 ? mInitialScale : mDefaultScale;
-        mInvActualScale = 1 / mActualScale;
+        mInitialScale = scaleInPercent * mDisplayDensity * 0.01f;
     }
 
     public final float computeScaleWithLimits(float scale) {
@@ -1120,7 +1114,6 @@ public void onFirstLayout(WebViewCore.DrawData drawData) {
             float scale;
             if (mInitialScale > 0) {
                 scale = mInitialScale;
-                mTextWrapScale = scale;
             } else if (viewState.mIsRestored) {
                 scale = (viewState.mViewScale > 0)
                     ? viewState.mViewScale : overviewScale;
@@ -1141,7 +1134,7 @@ public void onFirstLayout(WebViewCore.DrawData drawData) {
             }
             boolean reflowText = false;
             if (!viewState.mIsRestored) {
-                if (settings.getUseFixedViewport() && mInitialScale == 0) {
+                if (settings.getUseFixedViewport()) {
                     // Override the scale only in case of fixed viewport.
                     scale = Math.max(scale, overviewScale);
                     mTextWrapScale = Math.max(mTextWrapScale, overviewScale);