Add HyphenEdit to layout cache

We bypass the word layout cache for "complex" cases, which includes
things like OpenType features. We were counting a hyphen edit as such
a case, but the problem is that we measure a _lot_ of these when
doing layout with hyphenation.

This patch adds plumbing for hyphen edits to the layout cache, so
that word fragments with hyphens can be cached as well.

Bug: 22378829

Change-Id: Idba4df4faa14f48a5faccc8a7a7955a36c19ef27

include/minikin/MinikinFont.h

@@ -35,6 +35,7 @@ public:
     HyphenEdit() : hyphen(0) { }
     HyphenEdit(uint32_t hyphenInt) : hyphen(hyphenInt) { }
     bool hasHyphen() const { return hyphen != 0; }
+    bool operator==(const HyphenEdit &other) const { return hyphen == other.hyphen; }
 private:
     uint32_t hyphen;
 };
@@ -48,8 +49,7 @@ struct MinikinPaint {
             fakery(), fontFeatureSettings() { }
 
     bool skipCache() const {
-        // TODO: add hyphen to cache
-        return !fontFeatureSettings.empty() || hyphenEdit.hasHyphen();
+        return !fontFeatureSettings.empty();
     }
 
     MinikinFont *font;

libs/minikin/Layout.cpp

@@ -110,7 +110,7 @@ public:
             mStart(start), mCount(count), mId(collection->getId()), mStyle(style),
             mSize(paint.size), mScaleX(paint.scaleX), mSkewX(paint.skewX),
             mLetterSpacing(paint.letterSpacing),
-            mPaintFlags(paint.paintFlags), mIsRtl(dir) {
+            mPaintFlags(paint.paintFlags), mHyphenEdit(paint.hyphenEdit), mIsRtl(dir) {
     }
     bool operator==(const LayoutCacheKey &other) const;
     hash_t hash() const;
@@ -144,6 +144,7 @@ private:
     float mSkewX;
     float mLetterSpacing;
     int32_t mPaintFlags;
+    HyphenEdit mHyphenEdit;
     bool mIsRtl;
     // Note: any fields added to MinikinPaint must also be reflected here.
     // TODO: language matching (possibly integrate into style)
@@ -236,6 +237,7 @@ bool LayoutCacheKey::operator==(const LayoutCacheKey& other) const {
             && mSkewX == other.mSkewX
             && mLetterSpacing == other.mLetterSpacing
             && mPaintFlags == other.mPaintFlags
+            && mHyphenEdit == other.mHyphenEdit
             && mIsRtl == other.mIsRtl
             && mNchars == other.mNchars
             && !memcmp(mChars, other.mChars, mNchars * sizeof(uint16_t));
@@ -251,6 +253,7 @@ hash_t LayoutCacheKey::hash() const {
     hash = JenkinsHashMix(hash, hash_type(mSkewX));
     hash = JenkinsHashMix(hash, hash_type(mLetterSpacing));
     hash = JenkinsHashMix(hash, hash_type(mPaintFlags));
+    hash = JenkinsHashMix(hash, hash_type(mHyphenEdit.hasHyphen()));
     hash = JenkinsHashMix(hash, hash_type(mIsRtl));
     hash = JenkinsHashMixShorts(hash, mChars, mNchars);
     return JenkinsHashWhiten(hash);