Fix font size handling for harfbuzz hack

Complex languages (Arabic, Thai, etc.) currently need to override the
base font (e.g. Roboto)  with an explicitly loaded copy of the right
fallback font (e.g. DroidNaskh). To keep from running out of file
descriptors, a caching mechanism was put in place, but the cached
data contained the font size, so the first size seen on the page was
applied to all subsequent renderings of that font, regardless of the
size requested. Size is now also considered in the cache.

Bug: 5509443
Change-Id: I616954980122e89da14ce86efe99d5e4343a40c2

1 files changed, 15 insertions, 10 deletions

diff --git a/Source/WebCore/platform/graphics/android/FontAndroid.cpp b/Source/WebCore/platform/graphics/android/FontAndroid.cpp
index 3528d47..1e64873 100644
--- a/Source/WebCore/platform/graphics/android/FontAndroid.cpp
+++ b/Source/WebCore/platform/graphics/android/FontAndroid.cpp
@@ -59,6 +59,9 @@ using namespace android;
 
 namespace WebCore {
 
+typedef std::pair<int, float> FallbackFontKey;
+typedef HashMap<FallbackFontKey, FontPlatformData*> FallbackHash;
+
 static void updateForFont(SkPaint* paint, const SimpleFontData* font) {
     font->platformData().setupPaint(paint);
     paint->setTextEncoding(SkPaint::kGlyphID_TextEncoding);
@@ -454,7 +457,6 @@ private:
     };
 
     static const char* paths[NUM_SCRIPTS];
-    static const FontPlatformData* s_fallbackPlatformData[NUM_SCRIPTS];
 
     void setupFontForScriptRun();
     const FontPlatformData* setupComplexFont(CustomScript script,
@@ -509,9 +511,6 @@ const char* TextRunWalker::paths[] = {
     "/system/fonts/DroidSansHebrew-Bold.ttf"
 };
 
-// Indexed using enum CustomScript
-const FontPlatformData* TextRunWalker::s_fallbackPlatformData[] = {};
-
 TextRunWalker::TextRunWalker(const TextRun& run, unsigned startingX, const Font* font)
     : m_font(font)
     , m_startingX(startingX)
@@ -668,17 +667,23 @@ const FontPlatformData* TextRunWalker::setupComplexFont(
         CustomScript script,
         const FontPlatformData& platformData)
 {
-    if (!s_fallbackPlatformData[script]) {
+    static FallbackHash fallbackPlatformData;
+
+    FallbackFontKey key(script, platformData.size());
+    FontPlatformData* newPlatformData = 0;
+
+    if (!fallbackPlatformData.contains(key)) {
         SkTypeface* typeface = SkTypeface::CreateFromFile(paths[script]);
-        s_fallbackPlatformData[script] = new FontPlatformData(platformData, typeface);
+        newPlatformData = new FontPlatformData(platformData, typeface);
         SkSafeUnref(typeface);
+        fallbackPlatformData.set(key, newPlatformData);
     }
 
-    // If we couldn't allocate a new FontPlatformData, revert to the one passed
-    if (!s_fallbackPlatformData[script])
-        return &platformData;
+    if (!newPlatformData)
+        newPlatformData = fallbackPlatformData.get(key);
 
-    return s_fallbackPlatformData[script];
+    // If we couldn't allocate a new FontPlatformData, revert to the one passed
+    return newPlatformData ? newPlatformData : &platformData;
 }
 
 void TextRunWalker::setupFontForScriptRun()