aw: Skip hardware onDraw when visible rect is empty

android_webview/browser/browser_view_renderer.cc

Index: android_webview/browser/browser_view_renderer.cc
diff --git a/android_webview/browser/browser_view_renderer.cc b/android_webview/browser/browser_view_renderer.cc
index d9d3d0b1e18ab06b1eafcec9a9d45d6fd66dc6a8..c443a44af85350580ac44b9b318930b5b20351c8 100644
--- a/android_webview/browser/browser_view_renderer.cc
+++ b/android_webview/browser/browser_view_renderer.cc
@@ -46,7 +46,7 @@ const size_t kMemoryAllocationStep = 5 * 1024 * 1024;
 uint64 g_memory_override_in_bytes = 0u;
 
 // Used to calculate tile allocation. Determined experimentally.
-const size_t kTileMultiplier = 12;
+size_t kTileMultiplier = 12;
 const size_t kTileAllocationStep = 20;
 // This will be set by static function CalculateTileMemoryPolicy() during init.
 // See AwMainDelegate::BasicStartupComplete.
@@ -97,6 +97,8 @@ void BrowserViewRenderer::CalculateTileMemoryPolicy(bool use_zero_copy) {
 
     // Also use a high tile limit since there are no file descriptor issues.
     GlobalTileManager::GetInstance()->SetTileLimit(1000);
+
+    kTileMultiplier *= 2;

[hush (inactive), 2014/09/09 00:06:02]

why do we do this? By the way, if you want to double this, kTileMultiplier is
not a constant any more, so you need to rename the variable.

[boliu, 2014/09/09 00:07:19]

Ahh crap, unrelated change that I didn't mean to upload.

[hush (inactive), 2014/09/09 00:09:45]

cool. Get rid of this and other parts lgtm.
You need a bug number for this to merge into m38.
On 2014/09/09 00:07:19, boliu wrote:

     return;
   }
 
@@ -264,6 +266,9 @@ bool BrowserViewRenderer::OnDrawHardware(jobject java_canvas) {
   if (!compositor_)
     return false;
 
+  if (last_on_draw_global_visible_rect_.IsEmpty())
+    return client_->RequestDrawGL(java_canvas, false);
+
   if (!hardware_enabled_) {
     hardware_enabled_ = compositor_->InitializeHwDraw();
     if (hardware_enabled_) {