Cache auxiliary bitmap across draw frames

While this mode isn't intended to be used in anger, the slow down caused
by reallocating the temp bitmap every frame is very high even for a
development configuration.
Also add a bunch of useful tracing.

BUG=

Review URL: https://chromiumcodereview.appspot.com/15795002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@202035 0039d316-1c4b-4281-b951-d872f2087c98

3 files changed, 22 insertions, 8 deletions

diff --git a/android_webview/browser/browser_view_renderer.h b/android_webview/browser/browser_view_renderer.h
index 0251b26..f372256 100644
--- a/android_webview/browser/browser_view_renderer.h
+++ b/android_webview/browser/browser_view_renderer.h
@@ -53,7 +53,8 @@ class BrowserViewRenderer {
     virtual base::android::ScopedJavaLocalRef<jobject> CreateBitmap(
         JNIEnv* env,
         int width,
-        int height) = 0;
+        int height,
+        bool cache_result) = 0;
 
     // Draws the provided Java Bitmap into the provided Java Canvas.
     virtual void DrawBitmapIntoCanvas(
diff --git a/android_webview/browser/browser_view_renderer_impl.cc b/android_webview/browser/browser_view_renderer_impl.cc
index aacf9d4..72aaf39 100644
--- a/android_webview/browser/browser_view_renderer_impl.cc
+++ b/android_webview/browser/browser_view_renderer_impl.cc
@@ -342,7 +342,7 @@ bool BrowserViewRendererImpl::DrawSW(jobject java_canvas,
   if (!g_sw_draw_functions ||
       (pixels = g_sw_draw_functions->access_pixels(env, java_canvas)) == NULL) {
     ScopedJavaLocalRef<jobject> jbitmap(java_helper_->CreateBitmap(
-        env, clip.width(), clip.height()));
+        env, clip.width(), clip.height(), true));
     if (!jbitmap.obj())
       return false;
 
@@ -420,7 +420,7 @@ ScopedJavaLocalRef<jobject> BrowserViewRendererImpl::CapturePicture() {
   // If Skia versions are not compatible, workaround it by rasterizing the
   // picture into a bitmap and drawing it into a new Java picture.
   ScopedJavaLocalRef<jobject> jbitmap(java_helper_->CreateBitmap(
-      env, picture->width(), picture->height()));
+      env, picture->width(), picture->height(), false));
   if (!jbitmap.obj())
     return ScopedJavaLocalRef<jobject>();
 
diff --git a/android_webview/browser/in_process_renderer/in_process_view_renderer.cc b/android_webview/browser/in_process_renderer/in_process_view_renderer.cc
index 74acde0..e0b9e8f 100644
--- a/android_webview/browser/in_process_renderer/in_process_view_renderer.cc
+++ b/android_webview/browser/in_process_renderer/in_process_view_renderer.cc
@@ -9,6 +9,7 @@
 #include "android_webview/public/browser/draw_gl.h"
 #include "android_webview/public/browser/draw_sw.h"
 #include "base/android/jni_android.h"
+#include "base/debug/trace_event.h"
 #include "base/logging.h"
 #include "content/public/browser/android/content_view_core.h"
 #include "content/public/browser/render_view_host.h"
@@ -246,8 +247,11 @@ bool InProcessViewRenderer::DrawSWInternal(jobject java_canvas,
                                            const gfx::Rect& clip) {
   TRACE_EVENT0("android_webview", "InProcessViewRenderer::DrawSW");
 
-  if (clip.IsEmpty())
+  if (clip.IsEmpty()) {
+    TRACE_EVENT_INSTANT0("android_webview", "Empty Clip",
+                         TRACE_EVENT_SCOPE_THREAD);
     return true;
+  }
 
   JNIEnv* env = AttachCurrentThread();
 
@@ -256,14 +260,20 @@ bool InProcessViewRenderer::DrawSWInternal(jobject java_canvas,
       sw_functions->access_pixels(env, java_canvas) : NULL;
   // Render into an auxiliary bitmap if pixel info is not available.
   if (pixels == NULL) {
+    TRACE_EVENT0("android_webview", "Render to Aux Bitmap");
     ScopedJavaLocalRef<jobject> jbitmap(java_helper_->CreateBitmap(
-        env, clip.width(), clip.height()));
-    if (!jbitmap.obj())
+        env, clip.width(), clip.height(), true));
+    if (!jbitmap.obj()) {
+      TRACE_EVENT_INSTANT0("android_webview", "Bitmap Alloc Fail",
+                           TRACE_EVENT_SCOPE_THREAD);
       return false;
+    }
 
     if (!RasterizeIntoBitmap(env, jbitmap, clip.x(), clip.y(),
                              base::Bind(&InProcessViewRenderer::RenderSW,
                                         base::Unretained(this)))) {
+      TRACE_EVENT_INSTANT0("android_webview", "Rasterize Fail",
+                           TRACE_EVENT_SCOPE_THREAD);
       return false;
     }
 
@@ -334,9 +344,12 @@ InProcessViewRenderer::CapturePicture() {
   }
 
   // If Skia versions are not compatible, workaround it by rasterizing the
-  // picture into a bitmap and drawing it into a new Java picture.
+  // picture into a bitmap and drawing it into a new Java picture. Pass false
+  // for |cache_result| as the picture we create will hold a shallow reference
+  // to the bitmap drawn, and we don't want subsequent draws to corrupt any
+  // previously returned pictures.
   ScopedJavaLocalRef<jobject> jbitmap(java_helper_->CreateBitmap(
-      env, picture->width(), picture->height()));
+      env, picture->width(), picture->height(), false));
   if (!jbitmap.obj())
     return ScopedJavaLocalRef<jobject>();